Tuesday 12 November 2019

Niagara Falls Nature Club & Peninsula Field Naturalists

The Niagara Falls Nature Club has an active program to help people understand nature! [http://niagarafallsnatureclub.org/]

The Indoor Program is scheduled on the Second Wednesday of each month from September to May at 7:00 p.m. at the Niagara Falls Public Library, 4848 Victoria Avenue, Niagara Falls ON. Doors open by 6:40 for refreshments and social time.

Wednesday Evening Walks start in late April and extend to September.
See websie at [http://niagarafallsnatureclub.org/events/wednesday-evening-walks/]

Outings occur all year long on certain days. These take the form of day trips and an annual Weekend Long trip.

We also have in Niagara the Peninsula Field Naturalists program.

PENINSULA FIELD NATURALISTS

ADVOCATE,
EDUCATE and
PARTICIPATE

in the conservation of natural resources and green spaces in the Niagara Region and elsewhere.

Niagara Falls Nature Club
Bert Miller Nature Club
Buffalo Ornithological Society
Huron Fringe Birding Festival
Bird Studies Canada
MORE LINKS

Meetings held monthly
September - May

Niagara Region Headquarters
Committee Room 4
1815 Sir Isaac Brock Way
(formerly St. David’s Road West)
St Catharines, ON, Canada

Our outings continue throughout the year and there are plenty of family-friendly activities coming up this spring and summer.

Check our events and come on out and join us!

Most activities are FREE,
and all are welcome!

Birding , Hikes etc.

Would you like to join?

Peninsula Field Naturalists

Nature Walks

Friday 11 October 2019

Idiotic Environmental Predictions

[Editor:This article was written by Professor Walter E Williams but captures the facts better than 99.999% of the media which does not know enough to research truth but simply believes the panic-makers and joins the chorus of "The sky is falling! The sky is falling!"

And now for the article by Professor Williams ....

Idiotic Environmental Predictions

The Competitive Enterprise Institute has published a new paper, “Wrong Again: 50 Years of Failed Eco-pocalyptic Predictions.”

Keep in mind that many of the grossly wrong environmentalist predictions were made by respected scientists and government officials. My question for you is: If you were around at the time, how many government restrictions and taxes would you have urged to avoid the predicted calamity?

As reported in The New York Times (Aug. 1969) Stanford University biologist Dr. Paul Erhlich warned: “The trouble with almost all environmental problems is that by the time we have enough evidence to convince people, you’re dead. We must realize that unless we’re extremely lucky, everybody will disappear in a cloud of blue steam in 20 years.”

In 2000, Dr. David Viner, a senior research scientist at University of East Anglia’s climate research unit, predicted that in a few years winter snowfall would become “a very rare and exciting event. Children just aren’t going to know what snow is.”

In 2004, the U.S. Pentagon warned President George W. Bush that major European cities would be beneath rising seas.

Britain will be plunged into a Siberian climate by 2020.

In 2008, Al Gore predicted that the polar ice cap would be gone in a mere 10 years.

A U.S. Department of Energy study led by the U.S. Navy predicted the Arctic Ocean would experience an ice-free summer by 2016.

In May 2014, French Foreign Minister Laurent Fabius declared during a joint appearance with Secretary of State John Kerry that “we have 500 days to avoid climate chaos.”

Peter Gunter, professor at North Texas State University, predicted in the spring 1970 issue of The Living Wilderness:

“Demographers agree almost unanimously on the following grim timetable: by 1975 widespread famines will begin in India; these will spread by 1990 to include all of India, Pakistan, China and the Near East, Africa. By the year 2000, or conceivably sooner, South and Central America will exist under famine conditions. … By the year 2000, thirty years from now, the entire world, with the exception of Western Europe, North America, and Australia, will be in famine.”

Ecologist Kenneth Watt’s 1970 prediction was, “If present trends continue, the world will be about four degrees colder for the global mean temperature in 1990, but eleven degrees colder in the year 2000.” He added, “This is about twice what it would take to put us into an ice age.”

Mark J. Perry, scholar at the American Enterprise Institute and professor of economics and finance at the University of Michigan’s Flint campus, cites 18 spectacularly wrong predictions made around the time of first Earth Day in 1970.

This time it’s not about weather. Harrison Brown, a scientist at the National Academy of Sciences, published a chart in Scientific American that looked at metal reserves and estimated that humanity would run out of copper shortly after 2000. Lead, zinc, tin, gold and silver would be gone before 1990. Kenneth Watt said, “By the year 2000, if present trends continue, we will be using up crude oil at such a rate … that there won’t be any more crude oil.”

There were grossly wild predictions well before the first Earth Day, too. In 1939, the U.S. Department of the Interior predicted that American oil supplies would last for only another 13 years.

In 1949, the secretary of the interior said the end of U.S. oil supplies was in sight.

Having learned nothing from its earlier erroneous energy claims, in 1974, the U.S. Geological Survey said that the U.S. had only a 10-year supply of natural gas.

However, the U.S. Energy Information Administration estimated that as of Jan. 1, 2017, there were about 2,459 trillion cubic feet of dry natural gas in the United States. That’s enough to last us for nearly a century. The United States is the largest producer of natural gas worldwide.

Today’s wild predictions about climate doom are likely to be just as true as yesteryear’s.

The major difference is today’s Americans are far more gullible and more likely to spend trillions fighting global warming. And the only result is that we’ll be much poorer and less free.

Walter E. Williams is a professor of economics at George Mason University. To find out more about Walter E. Williams and read features by other Creators Syndicate writers and cartoonists, visit the Creators Syndicate webpage at www.creators.com.

Sunday 30 June 2019

Gender Identity Confusion?

Editor's Notes:
For those of us who are of mature years, can you believe that children are being taught "gender identity" in which they are taught that their gender may not coincide with their biological gender? Can you believe that a 6 year female student may be told that she may not be a "girl" in her gender identity?

In an effort to be "fair" to all children, does confusing those who already knew what gender they were born aid to enlightenment or stupidity?

This article is preserved here for the enlightenment, research, of those who may not have had the occasion to know about this article.

Barbara Kay: When gender identity education and theory goes wrong

A family is asking a school board to ensure that lessons do 'not devalue, deny, or undermine … the female gender identity'

A family has lodged a complaint with the Human Rights Tribunal of Ontario over the distress their six-year-old daughter experienced when informed by a teacher that gender is fluid and “girls are not real.”

In his recent commentary in these pages on the risks associated with the teaching of gender theories to elementary schoolchildren, Jordan Peterson referenced a column I wrote in another publication. The column concerned a human rights complaint, filed by Pamela and Jason Buffone on behalf of their daughter, “N,” against the Ottawa-Carleton District School Board for discrimination on the basis of gender and gender identity in contravention of the Human Rights Code.

Peterson faithfully summarized the story that led to the complaint, but readers may be interested in a few points about the complaint and the response from the school board’s lawyer that Peterson omitted as not directly salient to the thrust of his thesis.

To recap briefly: the Buffones’ daughter "N", six years old, and by their account a happy girl (comfortable in her skin, adored school), was abruptly plunged into considerable distress when informed by her teacher (young, three years experience) during a session on gender identity that gender is fluid and untethered to biology, and that “girls are not real” and “boys are not real.”

The lessons continued and so did N’s distress

The lessons continued and so did N’s distress, to the point of asking to see a doctor about her fears. The Buffones say in their claim that “they were concerned about the impact (on) N’s view of herself as a girl. Prior to (the teacher’s) discussions with the Grade One class, N had consistently identified as a girl and had not previously expressed uncertainty or discontent with her gender identity and biological sex.”

The Buffones had asked the teacher to affirm N’s identity as a girl — that is, reassure her that her identity as female was “real” in order to relieve her anxiety. Nothing that the Buffones asserted was denied by the school or its officials, but their request was rebuffed out of hand, first by the teacher, who said her lessons reflected “a change within society,” then by the principal, and all the way up the ladder to the superintendent of the school board and the curriculum superintendent.

They removed N to another school, where these gender theories are not taught, and where her mother told me she has recovered her wonted buoyancy.

In their Human Rights Tribunal of Ontario claim, the Buffones request as a remedy that the tribunal order the school board to ensure that classroom instruction does “not devalue, deny, or undermine in any way the female gender identity,” and that parents be informed “when lessons on gender identity will take place, including the teaching objectives and the materials that will be or have been used for such lessons.”

The response of the school board’s lawyers, who asked for dismissal of the complaint, state the claim has no reasonable basis for success. The lawyers note that teachers’ right to teach gender identity is endorsed by the minister of education, and that the “age-appropriateness of a classroom discussion does not engage a Code-protected prohibited ground.” That is to say, even if N was adversely affected by the teacher’s lessons — and they do not deny that this is the case — she has no grounds for redress according to the Human Rights Code.

If the school board is successful in its bid for dismissal, it means that the words “gender identity” and “gender expression” do not apply to everyone. They apply only to those whose gender identity does not synchronize with their biology — the protection of a biologically female child to identify as a girl would not be protected. Feelings of distress among the very small percentage of children whose gender identity differs from their biological sex must be alleviated at all cost. If that cost involves distress or confusion in the vast majority of other children like N, that is not “discrimination.”

The Buffones are not buying this (while acknowledging the human rights tribunal may well do so). The Ontario Human Rights Code takes a fairly broad view of discrimination. It states, for example, that a “poisoned environment” is a form of discrimination. The Buffones are “going to provide evidence that the manner in which (the teacher) was teaching the concept of gender identity resulted in a poisoned environment.”

It is clear that something is going terribly wrong with regard to gender teaching in Ontario classrooms.

I wish the Buffones well, and so do many other people. On social media many people applauded the Buffones’ courage in going public on behalf of other parents with similar stories who haven’t the confidence to take such a definitive step.

One respondent, who wishes anonymity, told me her son’s story, which bore similarities to N’s in that the child had never shown the slightest sign of gender confusion before lessons on gender theory began in school, with children being encouraged to identify along a spectrum rather than asserting they were either “girl” or “boy.” Out of the blue (I wish I had a dollar for every time I’ve heard this phrase used in this connection), he came home one day and announced he was “pansexual” and a “demi-girl.”

The parents took their son to see a psychologist. When she was told the name of the school and teacher, the therapist exclaimed, “You are the seventh set of parents from that class who have come to me with this problem!”

It is clear that something is going terribly wrong with regard to gender teaching in Ontario classrooms. Ontario must set up an investigative task force, composed of disinterested educators, disinterested gender researchers and parents, to objectively evaluate the teaching of gender identity in public schools.

• Email: kaybarb@gmail.com

Sunday 16 June 2019

Carbon Dioxide - The MORE the BETTER!

Carbon dioxide (CO2) is not carbon – and the difference is more than just a matter of knowing enough chemistry to distinguish an element from a compound. It's a matter of distinguishing a black solid that, in the form of fine soot particles, can cause respiratory diseases from an odorless, colorless gas that is non-toxic at any concentration and non-dangerous at concentrations 20 times the current 400 parts per million (ppm) in our atmosphere.

To call CO2 "carbon pollution" is not only bad chemistry and toxicology but also bad biology.

Carbon dioxide is essential to plant growth. The higher its concentration, the better plants grow. A study by researchers at the Technische Universität München found forests around the world growing up to 70 percent faster today than 50 years ago because of increased CO2.

As thousands of empirical studies have found, on average, every doubling of CO2 concentration in the atmosphere causes about a 35 percent increase in plant growth efficiency. Plants grow better in wetter and drier soils and in warmer and colder temperatures, widening their ranges and increasing their adaptability to climate changes, reducing the risk of biodiversity loss. They make better use of soil nutrients, resist diseases and pests better, and improve the ratio of fruit to fiber.

The consequence is more food for people and animals. Most important, it means more affordable food for the poor.

A review of refereed literature on the subject found the "monetary value of this benefit amount[ed] to a total sum of $3.2 trillion over the 50-year period 1961–2011. Projecting the monetary value … forward … reveals it will likely bestow an additional $9.8 trillion on crop production between now and 2050."

So any argument to reduce CO2 emissions must offset the fact that increasing CO2's concentration in the atmosphere enhances food production.

Advocates have their answer. It's all the negative "impacts" (note the pejorative) of the warming rising CO2 will cause. That takes us to the nub of the controversy: How much does added CO2 warm the atmosphere?

The U.N. Intergovernmental Panel on Climate Change suggests "climate sensitivity" (atmospheric warming in response to doubled CO2 concentration) of 1.5 C to 4.5 C.

That estimate of rests solely on the output of computer climate models. Their output is not data (raw observations of the external world) but hypotheses. So climate models' simulations aren't evidence of anything, they're guesses to be tested. And they fail.

On average, they simulate twice the warming observed over the relevant period. Over 95 percent simulate more warming than observed, so their errors are not random (evenly distributed above and below observations) but driven, intentionally or not, by bias. And none simulated the complete absence of warming over the last 18 years and 8 months.

Not surprisingly, top climate scientists have, as Georgia Tech climatologist Judith Curry has tracked on her blog, been reassessing "climate sensitivity," basing their estimates not on models but on empirical observation. They're tending, as the Cornwall Alliance for the Stewardship of Creation reported last year, toward estimates in the range of 0.3 C to 1.0 C (Nongovernmental International Panel on Climate Change) or 1.25 C to 3.0 C with a best estimate of 1.75˚ (Lewis and Crok). With those lower ranges, the "impacts" of "climate change" dwindle, and benefits might well outweigh costs.

So the models are wrong. Therefore they provide no rational basis for predicting future "global average temperature," or for calculating the "social cost of 'carbon' [dioxide]," or for any policy.

Reducing CO2 emissions would require less dependence on fossil fuels, which now provide over 85 percent of all the energy humans consume and are likely to continue to do so through probably the end of this century. But they are our best source for the abundant, affordable, reliable energy indispensable to any society's growing and staying out of poverty. Forcing the substitution of wind, solar and biofuels means raising the cost and reducing both the quantity and the reliability of energy available, which means slowing, stopping or reversing mankind's growth out of poverty.

It follows that we shouldn't embrace any such policy.

E. Calvin Beisner, Ph.D.
Founder and National Spokesman
The Cornwall Alliance for the Stewardship of Creation.

Ancient Trees

“They studied giant redwoods, the tallest trees on earth in Humboldt County California to reach these conclusions. They hypothesized and verified experimentally that as trees reached the height of 425 they could pump less and less water and nutrients up to new growth at that level. No current tree in the world has reached this height.

In effect, maximum tree growth is limited by gravity and friction.

Scientist George Koch and colleagues believe that they have established the upper limit for tree height. In an article entitled “Study Limits Maximum Tree Height”, by Jonathan Amos, which appeared in the BBC News Online in April 2004, that maximum tree height is about 425 feet.

Back in 1938, some scientists were speculating that the earth was shrinking and gravity along with it because of a huge petrified pine tree, well over three hundred feet tall found in the Rainbow Petrified Forest in Arizona.

In article sub-titled “Recent Discoveries in Petrified Forest Leads to Belief This Old Globe Is Gradually Contracting” (The Ogden Standard-Examiner, February 13. 1938) various scientists discussed the idea that at the time this petrified tree with its huge root system lived on the earth, its circumference was approximately 30,000 miles rather than the current 25,000. The larger earth would have exerted an attenuated (weaker) gravitational force on the trees and animals of that time.

According to the scientists quoted in the article,

“Since the newly discovered petrified tree Is of the Araucarias species, a form of pine which, when its sap is running, is of considerable weight, it probably weighed per lineal foot as much as modern-day smaller trees, and therefore seems to indicate that the magnetism and force of gravity of the earth at the’ time it grew were more dissipated, an indication that the earth itself possessed a greater diameter.”

These petrified trees had been transformed into onyx, jasper, agate, carnelian and chalcedony. Today, the giant redwoods are the growth champions. The various varieties of Araucarias would not have been expected to reach the same exalted heights.

The discovery that caused this scientific introspection occurred in 1938.

What the authors had overlooked in finding a petrified 300 foot plus tree of the Araucarias variety and finding themselves perplexed by it, is that a much larger tree had already been discovered in —Texas by federal geologists.

had been discovered in a petrified forest in Texas. According to an article in the Sunday, January 23, 1927 Port Arthur News, a petrified tree of the

Based on common sense, experience and the scientific article quoted herein establishing 425 feet as the upper limit for tree height, clearly something anomalous was going on in the distant past. Perhaps, more properly the earth’s current gravity is the anomaly.

According to the article, the forest is situated in a virtually inaccessible region in a valley of the Big Bend, nearly 100 miles from the nearest railroad spur at that time.

The forest was immodestly referred to as the greatest Petrified Forest known to man.

Mere stumps of trees rose 100 to 150 feet into the air. A thick covering of volcanic ash and pumice stone is said to have covered the trees and it is thought by the geologists/discoverers to have come from a volcano in the nearby Chisos mountains.

“One tree trunk measured 896 feet in length and the upright trunks are so large that they appear from a distance to be great symmetrical columns of natural rock. These federal geologists tell the -story. They have visited this distant valley, which is split by a deep arroyo leading into the Rio Grande.”

Clearly, if what this 1927 story reports is true, that 900 foot tree is more than twice that was projected by some scientists working in that field, as the maximum tree size obtainable in today’s gravity conditions. This means that gravity was somehow attenuated in the “distant” past.”

(I won’t rest until all of the greater-ancestors are found. Side Note: I was given a short list by an evolutionist during a debate and Redwood trees was on his list, previously it was on my difficulty-list along with rabbits, blue whales, as well as animals with giant in front of their name.) Chris L Lesley

Ooparts & Ancient High Technology website: http://s8int.com/-

by Greater Ancestors World Museum on Tuesday, April 5, 2011 at 10:35pm

Parent's Dilemma: I Hesitated to Vaccinate my Children - Mike Lake

[Editor: We publish this information for education, research, to benefit other parents who may have had the same problem as Mike Lake and his family. We take no credit for this information but wish to have it archived here for future reference of parents.]

Parents Dilemma

I hesitated to vaccinate my children. I know better now!

Mike Lake: Like all parents, we wanted to do the right thing. But one study, still thought to be credible at the time, made it harder to decide

The last week of April marks an interesting intersection in time. April is World Autism Month. The last week of April is also World Immunization Week. For many years now, there’s been a raging debate over the link between autism and vaccinations.

Robust, healthy debate is a core element of any strong society, but lately, this particular debate has become decidedly unhealthy. Though the evidence weighs strongly in favour of vaccines, the anti-vaccination movement uses compelling emotional arguments and the power of social media very well. The results are alarming, with parents increasingly opting out of safe and effective immunization for their children, fearing they might develop autism.

For context, in February of 1998, a British researcher named Andrew Wakefield co-authored a paper in The Lancet claiming to find a connection between autism and the MMR (measles, mumps, rubella) vaccine commonly used around the world.

Wakefield’s claims have since been thoroughly debunked by researchers worldwide. The paper was retracted by The Lancet, and Wakefield banned by the U.K.’s General Medical Council (GMC) from practicing medicine. The GMC report ruled that Wakefield was “dishonest, irresponsible and showed callous disregard” for children.

For me, this issue is very personal. In April 1998, just a couple of months after the publication of Wakefield’s study, my son Jaden was diagnosed with autism at age two-and-a-half. Like many parents receiving the news, his mother and I were desperate for answers. Jaden’s challenges were profound and seemed to have arisen suddenly. We wanted an explanation, and Wakefield’s research provided one, especially since Jaden had experienced a persistent fever in the hours after his first MMR shot a year earlier.

When our daughter, Jenae, was born in 1999, we were divided on how to deal with vaccines for both kids. Their mom wanted to wait. I disagreed, but still had my own questions. Like all parents, we wanted to do the right thing, and the Wakefield study, still thought to be credible then, made it harder to know just what that right thing was.

Luke Hendry/The Intelligencer/QMI Agency

In the end, we delayed vaccinations for both kids. Jenae received hers five years ago. And, as a happy result of conversations about my research for this article, we’ve looked into Jaden’s measles immunity and discovered that he needs one more shot, which he’ll get in the coming weeks.
We must understand some crucial facts about the life-saving benefits of vaccines.

We’re sharing our story now because it needs to be told. The significant noise created by a vocal minority is drowning out actual evidence that parents need as they sincerely try to make the best decisions they can for their kids.

Experts are united on this. The Canadian Paediatric Society states that “the MMR vaccine does not cause autism. There is no scientific evidence to support this claim.” The Centers for Disease Control and Prevention (CDC) in the U.S. has an entire page on its website under the unequivocal headline “Vaccines Do Not Cause Autism.”

There’s a rock-solid evidence base of major studies from around the world, involving millions of children. One 2015 study, published in the Journal of the American Medical Association, looked at over 95,000 children with older siblings, concluding that there is “no harmful association between MMR vaccine receipt and ASD.”

This week, the world’s top autism researchers are in Montreal for the 2019 International Society for Autism Research meeting. The meeting chair is Dr. Evdokia Anagnostou from Holland Bloorview Kids Rehabilitation Hospital in Toronto. Regarding autism, Dr. Anagnostou says, “There are many areas where we don’t have all the answers yet. However, this is not such an area. There is a very large body of research that has found no link between vaccines and autism.”

She continues, emphatically, “We’ve spent a lot of time and money researching a question we already know the answer to, because the public is worried. Research funding is limited. It’s important that we focus now on the many questions that still need answering.”

See Also

We must also understand some crucial facts about the life-saving benefits of vaccines.

Consider smallpox, thankfully something we don’t worry about today. Yet in 1966, there were more than 10 million cases worldwide and two million deaths in 43 countries. Just 11 years later, in 1977, the last known natural case of smallpox appeared in Somalia. It was eradicated, thanks to the systematic implementation of a science-based, global vaccination program.

Another tremendous success story is that of the fight against polio. In 1988, there were an estimated 350,000 cases in more than 125 countries. That year, the Global Polio Eradication Initiative was formed. Thirty-one years later, over three billion children have been vaccinated and polio is nearly wiped out, endemic in only three countries — Nigeria, Afghanistan and Pakistan. In 2018, there were just 33 cases worldwide, with advocates like Rotary International and Global Citizen (who encouraged me to write this piece) working with international leaders to finish the job.

In the case of measles, widespread immunization has driven a dramatic decrease in global mortality, down 80 per cent from approximately 545,000 deaths, mostly children, in 2000. It’s estimated that measles vaccination has saved more than 20 million lives in the past 20 years. However, this month, the World Health Organization reported that measles cases worldwide have quadrupled in 2019, with experts underscoring that this is partly due to the concerning spread of misinformation.

The next time you feel anxious about the state of our global health systems based on something you saw online, remember this fact: in 1955, global life expectancy was under 50 years. Today, it’s over 70 years. We must never stop striving to improve global health outcomes, but the data shows we are doing a lot of things right.

Finally, to parents, if you’ve heard or read things that have made you hesitant to vaccinate your kids, I totally understand. I’ve been there. But I’ve taken a hard look at the facts. I’ve spoken to the experts. And I no longer have those doubts. Vaccines do not cause autism. They have, however, saved hundreds of millions of lives worldwide. The evidence is overwhelmingly clear.

Mike Lake is the member of Parliament for Edmonton-Wetaskiwin.

Sunday 19 May 2019

Health Effects of Vegan Diets

Health effects of vegan diets

Winston J Craig

The American Journal of Clinical Nutrition, Volume 89, Issue 5, May 2009, Pages 1627S–1633S, https://doi.org/10.3945/ajcn.2009.26736N

Published:

11 March 2009

ABSTRACT

Recently, vegetarian diets have experienced an increase in popularity. A vegetarian diet is associated with many health benefits because of its higher content of fiber, folic acid, vitamins C and E, potassium, magnesium, and many phytochemicals and a fat content that is more unsaturated. Compared with other vegetarian diets, vegan diets tend to contain less saturated fat and cholesterol and more dietary fiber. Vegans tend to be thinner, have lower serum cholesterol, and lower blood pressure, reducing their risk of heart disease. However, eliminating all animal products from the diet increases the risk of certain nutritional deficiencies. Micronutrients of special concern for the vegan include vitamins B-12 and D, calcium, and long-chain n-3 (omega-3) fatty acids. Unless vegans regularly consume foods that are fortified with these nutrients, appropriate supplements should be consumed. In some cases, iron and zinc status of vegans may also be of concern because of the limited bioavailability of these minerals.

Issue Section:

Health and nutritional status of vegetarians

INTRODUCTION

A nationwide poll conducted in April 2006 by Harris Interactive reported that 1.4% of the American population is vegan, in that they eat no meat, fish, dairy, or eggs (1). Vegan diets are growing in popularity today among teenagers and youth, especially females. For many vegans, nutritional choices center around taking better care of the earth’s resources and the environment, ethical issues about animal care, the use of antibiotics and growth stimulants for the production of animals, the threat of animal-borne diseases, and the health advantages of a plant-based diet (2–6). In addition, the potential of allergies from dairy products and lactose intolerance have fueled the popularity of soy-based dairy substitutes.
What then is the nutritional and health status of those who follow a vegan diet? Compared with other vegetarians (eg, lactoovovegetarians), are there any advantages or disadvantages to following a vegan diet? Does the elimination of dairy and eggs offer any additional benefits or create potential concerns? The purpose of this brief review is to summarize current knowledge on the health effects of vegan diets, to discuss the nutritional concerns or shortfalls of a vegan diet and to provide some practical dietary recommendations for following a healthy vegan diet. Key et al (7) have provided a pertinent overview of the health effects of vegetarian diets, focusing on their European Prospective Investigation into Cancer and Nutrition–Oxford (EPIC-Oxford) study and other large population studies.

HEALTH EFFECTS OF VEGAN DIETS

Vegan diets are usually higher in dietary fiber, magnesium, folic acid, vitamins C and E, iron, and phytochemicals, and they tend to be lower in calories, saturated fat and cholesterol, long-chain n-3 (omega-3) fatty acids, vitamin D, calcium, zinc, and vitamin B-12 (8). In general, vegetarians typically enjoy a lower risk of cardiovascular disease (CVD), obesity, type 2 diabetes, and some cancers (3). A vegan diet appears to be useful for increasing the intake of protective nutrients and phytochemicals and for minimizing the intake of dietary factors implicated in several chronic diseases (9). In a recent report (10), different plant food groups were rated with respect to their metabolic-epidemiologic evidence for influencing chronic disease reduction. According to the evidence criteria of the World Health Organization and Food and Agriculture Organization (WHO/FAO), cancer risk reduction associated with a high intake of fruit and vegetables was assessed as probable or possible, risk of CVD reduction as convincing, whereas lower risk of osteoporosis was assessed as probable (10). The evidence for a risk-reducing effect of consuming whole grains was assessed as possible for colorectal cancer and probable for type 2 diabetes and CVD. The evidence for a risk-reducing effect of consuming nuts was assessed as probable for CVD (10).

Cardiovascular disease

In summarizing the published research, Fraser (11) noted that, compared with other vegetarians, vegans are thinner, have lower total and LDL cholesterol, and modestly lower blood pressure. This is true not only for whites; work by Toohey et al (12) showed that blood lipids and body mass index (BMI; in kg/m²) were significantly lower in African American vegans than in lactoovovegetarians. Similarly, among Latin Americans, vegetarians had lower plasma lipids than did their omnivore counterparts, with the lowest reported among vegans (13). In that study, plasma total and LDL cholesterol were 32% and 44% lower among vegans than among omnivores. Because obesity is a significant risk factor for CVD, the substantially lower mean BMI observed in vegans may be an important protective factor for lowering blood lipids and reducing the risk of heart disease (8).
Vegans, compared with omnivores, consume substantially greater quantities of fruit and vegetables (14–16). A higher consumption of fruit and vegetables, which are rich in fiber, folic acid, antioxidants, and phytochemicals, is associated with lower blood cholesterol concentrations (17), a lower incidence of stroke, and a lower risk of mortality from stroke and ischemic heart disease (18, 19). Vegans also have a higher consumption of whole grains, soy, and nuts (14, 15, 20), all of which provide significant cardioprotective effects (21, 22).

Cancer

Data from the Adventist Health Study showed that nonvegetarians had a substantially increased risk of both colorectal and prostate cancer than did vegetarians (23). A vegetarian diet provides a variety of cancer-protective dietary factors (24). In addition, obesity is a significant factor, increasing the risk of cancer at a number of sites (25). Because the mean BMI of vegans is considerably lower than that of nonvegetarians (8), it may be an important protective factor for lowering cancer risk.
Vegans consume considerably more legumes, total fruit and vegetables, tomatoes, allium vegetables, fiber, and vitamin C than do omnivores (14–16, 20, 23). All those foods and nutrients are protective against cancer (25). Fruit and vegetables are described as protective against cancer of the lung, mouth, esophagus, and stomach and to a lesser degree some other sites, whereas the regular use of legumes provides a measure of protection against stomach and prostate cancer. In addition, fiber, vitamin C, carotenoids, flavonoids, and other phytochemicals in the diet are shown to exhibit protection against various cancers, whereas allium vegetables provide protection against stomach cancer, and garlic against colorectal cancer. Foods rich in lycopene, such as tomatoes, are known to protect against prostate cancer (25).
Fruit and vegetables are known to contain a complex mixture of phytochemicals that possess potent antioxidant and antiproliferative activity and show additive and synergistic effects (24, 26). The phytochemicals interfere with several cellular processes involved in the progression of cancer. These mechanisms include inhibiting cell proliferation, inhibition of DNA adduct formation, inhibiting phase 1 enzymes, inhibiting signal transduction pathways and oncogene expression, inducing cell-cycle arrest and apoptosis, inducing phase 2 enzymes, blocking the activation of nuclear factor-κB, and inhibiting angiogenesis (24).
With this wide array of useful phytochemicals in the vegetarian diet, it is surprising that population studies have not shown more pronounced differences in cancer incidence or mortality rates between vegetarians and nonvegetarians (7, 27). The bioavailability of the phytochemicals, which depends among other things on food preparation methods, may be an important determining factor. However, new evidence suggests that a low vitamin D status, a problem often reported in vegan populations (8, 28), is associated with an increased risk of cancers (29, 30).
The sources of protein avoided or consumed by vegans also have definite health consequences. Red meat and processed meat consumption are consistently associated with an increase risk of colorectal cancer (25). Those in the highest quintile of red meat intake had elevated risks, ranging from 20% to 60%, of esophageal, liver, colorectal, and lung cancers than did those in the lowest quintile of red meat intake (31). In addition, the use of eggs was recently shown to be associated with a higher risk of pancreatic cancer (32). Although vegans avoid consuming red meat and eggs altogether, they consume greater amounts of legumes than do omnivores (14, 16, 20). This protein source was seen in the Adventist Health Study to be negatively associated with risk of colon cancer (23). New data suggest that legume intake is also associated with a moderate reduction in the risk of prostate cancer (33). In Western society, vegans also consume substantially more tofu and other soy products than do omnivores (14, 16). Consumption of isoflavone-containing soy products during childhood and adolescence protects women against the risk of breast cancer later in life (34), whereas a high childhood dairy intake has been associated with an elevated risk of colorectal cancer in adulthood (35). Cancer risk in vegans may be altered because vegans consume soy beverages rather than dairy beverages. Data from the Adventist Health Study showed that consumption of soy milk by vegetarians protected them against prostate cancer (36), whereas in other studies the use of dairy was associated with an increased risk of prostate cancer (25, 37–39).
Further research is needed to explore the relation between consuming plant-based diets and risk of cancer because there are many unanswered questions about how diet and cancer are connected. To date, epidemiologic studies have not provided convincing evidence that a vegan diet provides significant protection against cancer. Although plant foods contain many chemopreventive factors, most of the research data comes from cellular biochemical studies.

Bone health

Cross-sectional and longitudinal population-based studies published within the past 2 decades suggest no differences in bone mineral density (BMD), for both trabecular and cortical bone, between omnivores and lactoovovegetarians (40). More recent studies with postmenopausal Asian women showed spine or hip BMD was significantly lower in long-term vegans (41, 42). Those Asian women, who were vegetarian for religious reasons, had low intakes of protein and calcium. An inadequate protein and low calcium intake has been shown to be associated with bone loss and fractures at the hip and spine in the elderly (43, 44). Adequate calcium intake may be a problem for vegans. Although lactoovovegetarians generally consume adequate amounts of calcium, vegans typically fall short of the recommended daily intake for calcium (8, 45, 46). Results from the EPIC-Oxford study provide good evidence that the risk of bone fractures for vegetarians was similar to that of omnivores (46). The higher risk of bone fracture seen in vegans appears to be a consequence of a lower mean calcium intake. No difference was observed between the fracture rates of the vegans who consumed >525 mg calcium/d and the omnivore fracture rates (46).
Bone health depends on more than just protein and calcium intakes. Research has shown that bone health is also influenced by nutrients such as vitamin D, vitamin K, potassium, and magnesium and by foods such as soy and fruit and vegetables (47–50). Vegan diets do well in providing a number of those important substances. The maintenance of acid-base balance is critical for bone health. A drop in extracellular pH stimulates bone resorption (51), because bone calcium is used to buffer the pH drop. An acid-forming diet, therefore, increases urinary calcium excretion (52). However, a diet rich in fruit and vegetables that is typical of a vegan diet has a positive effect on the calcium economy and markers of bone metabolism in men and women (49). The high potassium and magnesium content of fruit and vegetables provides an alkaline ash, which inhibits bone resorption (53). Higher intakes of potassium are associated with greater BMD of the femoral neck and lumbar spine of premenopausal women (54).
Blood concentrations of undercarboxylated osteocalcin, a sensitive marker of vitamin K status, is considered an indicator of hip fracture (55) and a predictor of BMD (56). Results from 2 large, prospective cohort studies support an association between vitamin K intake and relative risk of hip fracture. In the Nurses’ Health Study, middle-aged women consuming the most vitamin K had the lowest risk of hip fracture. Risk of hip fracture was decreased 45% for ≥1 servings/d of green leafy vegetables (the main vitamin K source) compared with ≤1 serving/wk (57). In the Framingham Heart Study, elderly men and women in the highest quartile of vitamin K intake had a 65% decreased risk of hip fracture than did those in the lowest quartile (58).
In addition to a high intake of fruit and vegetables, vegans also tend to have a high intake of tofu and other soy products (14, 16). Soy isoflavones are suggested to have a beneficial effect on bone health in postmenopausal women (50). In a meta-analysis of 10 randomized controlled trials, soy isoflavones showed a significant benefit to spine BMD of menopausal women (59). In another meta-analysis, soy isoflavones significantly inhibited bone resorption and stimulated bone formation compared with placebo (60). In a randomized clinical trial lasting 24 mo involving osteopenic postmenopausal women, increases in BMD of both lumbar spine and femoral neck were substantially greater with the soy isoflavone, genistein, than with placebo (61).
As long as the calcium and vitamin D intake of vegans is adequate, their bone health is probably not an issue because their diet contains an ample supply of other protective factors for bone health. However, more studies are needed to provide more definitive data on the bone health of vegans.

POTENTIAL NUTRITIONAL SHORTFALLS

To obtain a nutritionally adequate diet, the consumer must first have an appropriate knowledge of what constitutes a nutritionally adequate diet. Second, accessibility is important, ie, the availability of certain foodstuffs and foods fortified with key nutrients that are otherwise lacking in the diet. This accessibility will vary greatly, depending on the geographic region of the world, because different countries have different fortification laws. The following section deals with nutrients of concern in the vegan diet. The problem of insufficient calcium has already been discussed in the section on bone health.

n-3 Polyunsaturated fat

Diets that do not include fish, eggs, or sea vegetables (seaweeds) generally lack the long-chain n-3 fatty acids, eicosapentaenoic acid (EPA; 20:5n-3) and docosahexaenoic acid (DHA; 22:6n-3), which are important for cardiovascular health as well as eye and brain functions. The plant-based n-3 fatty acid α-linolenic acid (ALA; 18:3n-3) can be converted into EPA and DHA, albeit with a fairly low efficiency (62, 63). Compared with nonvegetarians, vegetarians, and especially vegans, tend to have lower blood concentrations of EPA and DHA (64). However, vegans can obtain DHA from microalgae supplements containing DHA, as well as from foods fortified with DHA. However, EPA can be obtained from the retroconversion of DHA in the body. The oil from brown algae (kelp) has also been identified as a good source of EPA.
The new Dietary Reference Intakes recommend intakes of 1.6 and 1.1 g ALA/d for men and women, respectively, which accounts for <1% of the daily calories. Presently, the intake of EPA plus DHA in the United States is only 0.1–0.2 g/d, with the DHA intake being ≈2–3 times the intake of EPA (65). Vegans should be able to easily reach the n-3 fatty acid requirements by including regular supplies of ALA-rich foods in their diet and also DHA-fortified foods and supplements. However, DHA supplements should be taken with caution. Although they can lower plasma triacylglycerol, they can raise total and LDL cholesterol (66, 67), cause excessively prolonged bleeding times, and impair immune responses (65).

Vitamin D

In the EPIC-Oxford study, vegans had the lowest mean intake of vitamin D (0.88 μg/d), a value one-fourth the mean intake of omnivores (8). For a vegan, vitamin D status depends on both sun exposure and the intake of vitamin D-fortified foods. Those living in areas of the world without fortified foods would need to consume a vitamin D supplement. Living at high latitudes can also affect one’s vitamin D status, because sun exposure in that region is inadequate for several months of the year (68). Those who are dark skinned, elderly, who extensively cover their body with clothing for cultural reasons, and who commonly use sunscreen are at an increased risk of vitamin D deficiency (45). Another matter of concern for vegans is that vitamin D₂, the form of vitamin D acceptable to vegans, is substantially less bioavailable than the animal-derived vitamin D₃ (69).
In Finland, the dietary intake of vitamin D in vegans was insufficient to maintain serum 25-hydroxyvitamin D and parathyroid hormone concentrations within normal ranges in the winter, which appeared to have a negative effect on long-term BMD (28). Throughout the year serum 25-hydroxyvitamin D concentrations were lower and parathyroid hormone higher in vegan women than in omnivores and other vegetarians. BMD in the lumbar region of the spine was 12% lower in vegans than in omnivores.

Iron

Heme iron absorption is substantially higher than non-heme iron from plant foods. However, hemoglobin concentrations and the risk of iron deficiency anemia are similar for vegans compared with omnivores and other vegetarians (70). Vegans often consume large amounts of vitamin C–rich foods that markedly improve the absorption of the nonheme iron. Serum ferritin concentrations are lower in some vegans, whereas the mean values tend to be similar to the mean values of other vegetarians but lower than the mean value for omnivores (71). The physiologic significance of low serum ferritin concentrations is uncertain at this time.

Vitamin B-12

Compared with lactoovovegetarians and omnivores, vegans typically have lower plasma vitamin B-12 concentrations, higher prevalence of vitamin B-12 deficiency, and higher concentrations of plasma homocysteine (72). Elevated homocysteine has been considered a risk factor for CVD (73) and osteoporotic bone fractures (74). Vitamin B-12 deficiency can produce abnormal neurologic and psychiatric symptoms that include ataxia, psychoses, paresthesia, disorientation, dementia, mood and motor disturbances, and difficulty with concentration (75). In addition, children may experience apathy and failure to thrive, and macrocytic anemia is a common feature at all ages.

Zinc

Vegetarians are often considered to be at risk for zinc deficiency. Phytates, a common component of grains, seeds, and legumes, binds zinc and thereby decreases its bioavailability. However, a sensitive marker to measure zinc status in humans has not been well established, and the effects of marginal zinc intakes are poorly understood (76). Although vegans have lower zinc intake than omnivores, they do not differ from the nonvegetarians in functional immunocompetence as assessed by natural killer cell cytotoxic activity (14). It appears that there may be facilitators of zinc absorption and compensatory mechanisms to help vegetarians adapt to a lower intake of zinc (77).

DIETARY RECOMMENDATIONS FOR OPTIMAL VEGAN DIETS

1) To avoid B-12 deficiency, vegans should regularly consume vitamin B-12–fortified foods, such as fortified soy and rice beverages, certain breakfast cereals and meat analogs, and B-12–fortified nutritional yeast, or take a daily vitamin B-12 supplement. Fermented soy products, leafy vegetables, and seaweed cannot be considered a reliable source of active vitamin B-12. No unfortified plant food contains any significant amount of active vitamin B-12.
2) To ensure adequate calcium in the diet, calcium-fortified plant foods should be regularly consumed in addition to consuming the traditional calcium sources for a vegan (green leafy vegetables, tofu, tahini). The calcium-fortified foods include ready-to-eat cereals, calcium-fortified soy and rice beverages, calcium-fortified orange and apple juices, and other beverages. The bioavailability of the calcium carbonate in the soy beverages and the calcium citrate malate in apple or orange juice is similar to that of the calcium in milk (78, 79). Tricalcium phosphate–fortified soy milk was shown to have a slightly lower calcium bioavailability than the calcium in cow milk (78).
3) To ensure an adequate vitamin D status, especially during the winter, vegans must regularly consume vitamin D–fortified foods such as soy milk, rice milk, orange juice, breakfast cereals, and margarines that are fortified with vitamin D. Where fortified foods are unavailable, a daily supplement of 5–10 μg vitamin D would be necessary. The supplement would be highly desirable for elderly vegans.
4) A vegan should regularly consume plant foods naturally rich in the n-3 fatty acid ALA, such as ground flaxseed, walnuts, canola oil, soy products, and hemp seed–based beverages. In addition, it is recommended that vegans consume foods that are fortified with the long-chain n-3 fatty acid DHA, such as some soy milks and cereal bars. Those with increased requirements of long-chain n-3 fatty acids, such as pregnant and lactating women, would benefit from using DHA-rich microalgae supplements.
5) Because of the high phytate content of a typical vegan diet, it is important that a vegan consume foods that are rich in zinc, such as whole grains, legumes, and soy products, to provide a sufficient zinc intake. Benefit could also be obtained by vegans consuming fortified ready-to-eat cereals and other zinc-fortified foods.

A more comprehensive list of eating guidelines for vegans is available elsewhere (80).

FURTHER RESEARCH NEEDED

The term vegetarian is often used to describe a whole range of diets practiced with varying degrees of restriction, making it a challenge to meaningfully compare and contrast the health benefits of various vegetarian diets. Although preliminary data are valuable, more scientific studies on vegans are needed to get a clearer picture of their health status (7, 11). Current data show that vegans have a lower risk of heart disease than do omnivores and other vegetarians, but there are too few studies on other risk factors for definitive conclusions. One small pilot trial has shown that a vegan diet improves glycemic control in individuals with type 2 diabetes (81), but more studies are needed that look at the effects of a vegan diet on the risk of diabetes, as well as cancer. On the basis of our present knowledge, vegans do not appear likely to have any significant advantages over other vegetarians about chronic disease patterns (11). The vegan studies that do exist often involve only a small number of subjects. More studies are also needed with long-term vegans because the health advantages appear more clearly defined when a person has been following a plant-based diet for >5 y (82). Research is also needed to investigate whether the age at which a vegan diet is adopted has any influence on health outcomes.

SUMMARY

Vegans are thinner, have lower serum cholesterol and blood pressure, and enjoy a lower risk of CVD. BMD and the risk of bone fracture may be a concern when there is an inadequate intake of calcium and vitamin D. Where available, calcium- and vitamin D–fortified foods should be regularly consumed. There is a need for more studies on the relation between vegan diets and risk of cancer, diabetes, and osteoporosis. Vitamin B-12 deficiency is a potential problem for vegans, so that the use of vitamin B-12–fortified foods or supplements are essential. To optimize the n-3 fatty acid status of vegans, foods rich in ALA, DHA-fortified foods, or DHA supplements should be regularly consumed. Vegans generally have an adequate iron intake and do not experience anemia more frequently than others. Typically, vegans can avoid nutritional problems if appropriate food choices are made. Their health status appears to be at least as good as other vegetarians, such as lactoovovegetarians. (Other articles in this supplement to the Journal include references 83–109.)
The author had no financial disclosures to report.

FOOTNOTES

Presented at the symposium, “Fifth International Congress on Vegetarian Nutrition,” held in Loma Linda, CA, March 4–6, 2008.

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