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In an article that may bring smiles to the faces of vegetarians who consume no dairy products and vegans, who consume no animal-based foods, scientists have identified seaweed as a rich new potential source of heart-healthy food ingredients. Seaweed and other “macroalgae” could rival milk products as sources of these so-called “bioactive peptides,” they conclude in an article in ACS’s Journal of Agricultural and Food Chemistry.

Maria Hayes and colleagues Ciarán Fitzgerald, Eimear Gallagher and Deniz Tasdemir note increased interest in using bioactive peptides, now obtained mainly from milk products, as ingredients in so-called functional foods. Those foods not only provide nutrition, but have a medicine-like effect in treating or preventing certain diseases. Seaweeds are a rich but neglected alternative source, they state, noting that people in East Asian and other cultures have eaten seaweed for centuries: Nori in Japan, dulse in coastal Europe, and limu palahalaha in native Hawaiian cuisine.

Their review of almost 100 scientific studies concluded that that some seaweed proteins work just like the bioactive peptides in milk products to reduce blood pressure almost like the popular ACE inhibitor drugs.  “The variety of macroalga species and the environments in which they are found and their ease of cultivation make macroalgae a relatively untapped source of new bioactive compounds, and more efforts are needed to fully exploit their potential for use and delivery to consumers in food products,” Hayes and her colleagues conclude.

Older people who use olive oil in their cooking and on their salads may have a lower risk of suffering a stroke, researchers reported Wednesday.

In a study that followed older French adults for five years, researchers found that those who regularly used olive oil were 41 percent less likely to have a stroke than those who never used the oil.

The findings, reported in the journal Neurology, hint that the well-known connection between olive oil and heart disease might extend to stroke as well. Olive oil is a key ingredient in the so-called Mediterranean diet. And some clinical trials have suggested that the diet helps control risk factors for heart disease, like high blood pressure, abdominal obesity and elevated levels of “bad” LDL cholesterol.

High olive oil intake is also linked to a lower risk of heart attack, and a longer lifespan among heart attack survivors. These latest findings support the general advice that people replace dubious dietary fats — namely, saturated fats and “trans” fats — with olive oil and other unsaturated fats, according to an expert not involved in the study. But he also stressed that the study does not prove that olive oil, per se, helps prevent strokes.

“We need to remember that this is an observational study,” said Dr. Nikolaos Scarmeas, a neurologist at Columbia University Medical Center in New York who wrote an editorial published with the study.

The study found a correlation between people’s olive oil use and their stroke risk, he told Reuters Health — but that doesn’t necessarily translate into cause-and-effect.

“People who use a lot of olive oil may be very different from people who don’t,” Scarmeas said.

Olive oil users may, for example, have higher incomes, eat better overall or exercise more often than people who never use the oil. The researchers on the new study, led by Cécilia Samieri of the French national research institute INSERM, tried to account for those differences. And after they did, olive oil was still linked to a lower stroke risk.

But it’s impossible to fully account for all those variables, Scarmeas noted. What’s needed, he said, are clinical trials where people are randomly assigned to use olive oil or not, then followed over time to see who suffers a stroke. Such clinical trials are considered the “gold standard” of medical evidence.

The current study included 7,625 French adults age 65 and older who reported on their diets and other lifestyle factors. People who said they used olive oil for both cooking and as a dressing were considered “intensive users.”

Over the next five to six years, those intensive users suffered strokes at a rate of 0.3 percent per year. That compared with just over 0.5 percent among non-users, and 0.4 percent among moderate users.

When the researchers factored in other diet habits, exercise levels and major risk factors for stroke — like high blood pressure and diabetes — heavy olive oil use was tied to 41 percent reduction in the odds of stroke.

Samieri’s team also took blood samples from another 1,245 older adults, measuring their levels of oleic acid — a monounsaturated fat that accounts for most of the fatty acids in olive oil. The one-third of participants with the highest oleic acid levels were 73 percent less likely to suffer a stroke than the one-third with the lowest levels.

The findings, according to Scarmeas, argue for more research into olive oil’s potential benefits against not only heart disease, but stroke and other neurological diseases as well.

For now, he suggested that people choose olive oil and other unsaturated fats over saturated fats (found largely in meat and dairy) and trans fats (found in some processed foods, like crackers, cookies and chips).

“It’s better to rely on this type of fat for your overall health,” Scarmeas said.

That said, no single food is consumed in isolation, he points out in his editorial. Olive oil is one part of the Mediterranean diet that has been tied to heart benefits. The diet also boasts plenty of fruits and vegetables, legumes, whole grains, fish and moderate amounts of red wine.

SOURCE: Neurology, online June 15, 2011

Overweight and obese people looking to drop some pounds and considering one of the popular low-carbohydrate diets, along with moderate exercise, need not worry that the higher proportion of fat in such a program compared to a low-fat, high-carb diet may harm their arteries, suggests a pair of new studies by heart and vascular researchers at Johns Hopkins.

“Overweight and obese people appear to really have options when choosing a weight-loss program, including a low-carb diet, and even if it means eating more fat,” says the studies’ lead investigator exercise physiologist Kerry Stewart, Ed.D.

Stewart, a professor of medicine and director of clinical and research exercise physiology at the Johns Hopkins University School of Medicine and its Heart and Vascular Institute, says his team’s latest analysis is believed to be the first direct comparison of either kind of diet on the effects to vascular health, using the real-life context of 46 people trying to lose weight through diet and moderate exercise. The research was prompted by concerns from people who wanted to include one of the low-carb, high-fat diets, such as Atkins, South Beach and Zone, as part of their weight-loss program, but were wary of the diets’ higher fat content.

In the first study, scheduled to be presented June 3 at the annual meeting of the American College of Sports Medicine in Denver, the Hopkins team studied 23 men and women, weighing on average 218 pounds and participating in a six-month weight-loss program that consisted of moderate aerobic exercise and lifting weights, plus a diet made up of no more than 30 percent of calories from carbs, such as pastas, breads and sugary fruits. As much as 40 percent of their diet was made up of fats coming from meat, dairy products and nuts. This low-carb group showed no change after shedding 10 pounds in two key measures of vascular health: finger tip tests of how fast the inner vessel lining in the arteries in the lower arm relaxes after blood flow has been constrained and restored in the upper arm (the so-called reactive hyperemia index of endothelial function), and the augmentation index, a pulse-wave analysis of arterial stiffness.

Low-carb dieters showed no harmful vascular changes, but also on average dropped 10 pounds in 45 days, compared to an equal number of study participants randomly assigned to a low-fat diet. The low-fat group, whose diets consisted of no more than 30 percent from fat and 55 percent from carbs, took on average nearly a month longer, or 70 days, to lose the same amount of weight.

“Our study should help allay the concerns that many people who need to lose weight have about choosing a low-carb diet instead of a low-fat one, and provide re-assurance that both types of diet are effective at weight loss and that a low-carb approach does not seem to pose any immediate risk to vascular health,” says Stewart. “More people should be considering a low-carb diet as a good option,” he adds.

Because the study findings were obtained within three months, Stewart says the effects of eating low-carb, higher-fat diets versus low-fat, high-carb options over a longer period of time remain unknown.

However, Stewart does contend that an over-emphasis on low-fat diets has likely contributed to the obesity epidemic in the United States by encouraging an over-consumption of foods high in carbohydrates. He says high-carb foods are, in general, less filling, and people tend to get carried away with how much low-fat food they can eat. More than half of all American adults are estimated to be overweight, with a body mass index, or BMI, of 26 or higher; a third are considered to be obese, with a BMI of 30 or higher.

Stewart says the key to maintaining healthy blood vessels and vascular function seems – in particular, when moderate exercise is included — less about the type of diet and more about maintaining a healthy body weight without an excessive amount of body fat.

Among the researchers’ other key study findings, to be presented separately at the conference, was that consuming an extremely high-fat McDonald’s breakfast meal, consisting of two English muffin sandwiches, one with egg and another with sausage, along with hash browns and a decaffeinated beverage, had no immediate or short-term impact on vascular health. Study participants’ blood vessels were actually less stiff when tested four hours after the meal, while endothelial or blood vessel lining function remained normal.

Researchers added the McDonald’s meal challenge immediately before the start of the six-month investigation to separate any immediate vascular effects from those to be observed in the longer study. They also wanted to see what happened when people ate a higher amount of fat in a single meal than recommended in national guidelines. Previous research had suggested that such a meal was harmful, but its negative findings could not be confirmed in the Johns Hopkins’ analysis. The same meal challenge will be repeated at the end of the study, when it is expected that its participants will still have lost considerable weight, despite having eaten more than the recommended amount of fat.

“Even consuming a high-fat meal now and then does not seem to cause any immediate harm to the blood vessels,” says Stewart. However, he strongly cautions against eating too many such meals because of their high salt and caloric content. He says this single meal — at over 900 calories and 50 grams of fat — is at least half the maximum daily fat intake recommended by the American Heart Association and nearly half the recommended average daily intake of about 2,000 calories for most adults.

All study participants were between the age of 30 and 65, and healthy, aside from being overweight or obese. Researchers say that in the first study, because people were monitored for the period they lost the same amount of weight, any observed vascular differences would be due to what they ate.

Funding for the study was provided by the National Institute of Diabetes and Digestive and Kidney Diseases, part of the National Institutes of Health (NIH), with additional assistance from the Johns Hopkins Bayview Institute for Clinical Translational Research, also funded by the NIH. Besides Stewart, other Johns Hopkins researchers who took part in the studies were Sameer Chaudri, M.D.; Devon Dobrosielski, Ph.D.; Harry Silber, M.D., Ph.D.; Sammy Zakaria, M.D., M.P.H.; Edward Shapiro, M.D.; and Pamela Ouyang, M.B.B.S.

PROVIDENCE, R.I. [Brown University] —Dairy products can be high in harmful saturated fat but not necessarily in risk to the heart. A newly published analysis of thousands of adults in Costa Rica found that their levels of dairy consumption had nothing to do statistically with their risk of a heart attack.

“Things like milk and cheese are very complex substances,” said Stella Aslibekyan, a community health graduate student at Brown University and the lead author of the study, published in advance online May 4 in the journal Nutrition, Metabolism and Cardiovascular Diseases. “We looked at [heart attack risk and] dairy products in their entirety and then looked at separate components of those dairy products, including fats, and it turns out that the results are null. Perhaps the evidence is not there.”

Rather than suggesting that the saturated fats in dairy products are harmless, Aslibekyan and co-author Ana Baylin, an adjunct assistant professor of community health at Brown, hypothesize that other nutrients in dairy products are protective against heart disease, for all but perhaps the highest dairy consumption quintile in their study. The potentially beneficial nutrients include calcium, vitamin D, potassium, magnesium and conjugated linoleic acid (CLA).

To conduct the study, Aslibekyan and Baylin analyzed data on 3,630 middle-aged Costa Rican men and women who participated in an epidemiological study between 1994 and 2004 by co-author Hannia Campos of the Harvard School of Public Health.

They split the study population between two equal groups: 1,815 “cases” who had non-fatal heart attacks and 1,815 comparable “controls” who did not. The researchers looked not only at the subjects’ self-reported dairy intake, but also at measurements of dairy fat biomarkers, namely 15:0 and 17:0, in their bodies.

What they found is that the dairy intake of people who had heart attacks was not statistically different than the intake of people who did not. After breaking people into quintiles, based on their dairy consumption amount, there was no significant linear relationship between consumption and heart risk, even among the most voracious consumers. The highest consumption quintile consumed an average of 593 grams of dairy foods a day.

When the researchers controlled for such risk factors as smoking, waist-to-hip ratio, alcohol intake, and physical activity, the lack of a statistically significant association between dairy intake and heart attack risk remained. They also tracked and adjusted the data for levels of CLA and calcium and found they may have a protective effect. Protective effects lessened in the highest quintile, however.

Baylin likened the nutritional complexity of dairy products to that of eggs, which were once a source of intense consumer concern because of their cholesterol content, but are now viewed in a more complex way because they, too, have seemingly protective nutrients.

“The message is that it is important to look at the net effect of whole foods and dietary patterns and not only isolated nutrients”  Baylin said.

Since conducting the study at Brown, Baylin has been appointed an assistant professor of epidemiology at the University of Michigan School of Public Health. Aslibekyan, who will graduate from Brown May 29 with a PhD, is already employed as a postdoctoral scholar at the University of Alabama at Birmingham.

The National Institutes of Health funded the research with grant HL60692.

CLEVELAND – Contrary to what we’ve been told, eliminating or severely limiting fats from the diet may not be beneficial to cardiac function in patients suffering from heart failure, a study at Case Western Reserve University School of Medicine reports. Results from biological model studies conducted by assistant professor of physiology and biophysics Margaret Chandler, PhD, and other researchers, demonstrate that a high-fat diet improved overall mechanical function, in other words, the heart’s ability to pump, and was accompanied by cardiac insulin resistance.

“Does that mean I can go out and eat my Big Mac after I have a heart attack,” Dr. Chandler says “No, but treatments that act to provide sufficient energy to the heart and allow the heart to utilize or to maintain its normal metabolic profile may actually be advantageous.”

The research, published in American Journal of Physiology-Heart and Circulatory Physiology, suggests that for a damaged heart, a balanced diet that includes mono- and polyunsaturated fats, and which replaces simple sugars (sucrose and fructose) with complex carbohydrates, may be beneficial.

In a healthy person, the heart uses both fats and carbohydrates to obtain the energy it needs to continue pumping blood 24/7. Ideally, fats are utilized because they yield more energy. However, if a person develops heart failure (or suffers from ischemia – a lack of blood supply), the heart seems to prefer using glucose for fuel, because glucose requires less oxygen to produce energy. While heart disease remains the leading cause of death in the United States, more people are surviving heart attacks that ever before. Survivors though pay a price for this improved survival, living with a damaged heart that usually progresses to heart failure. And unfortunately, medications and procedures have yet to “cure” heart failure, or halt the deterioration of heart function.

Upon initiation of these dietary intervention studies, researchers previously thought a high-fat diet fed to animal models that have suffered a heart attack, would overload their tissues with fat, which in turn would have a toxic effect on their hearts. Surprisingly, the heart’s pump function improved on the high-fat diet. Through further testing, the researchers found that animal models suffering from heart failure and receiving a low fat diet were able to produce insulin and take up glucose from the blood, just as healthy hearts do.

However, the biological models with heart failure that were fed high-fat diets showed signs of insulin resistance, exhibited by a decreased amount of glucose taken up by the heart, as might be expected in a diabetic patient. One of the main implications of these findings is that contrary to previously held beliefs, a state of insulin-resistance might actually be beneficial to a failing heart. The hypothesis, according to Dr. Chandler, is that because the heart is being provided with excess amounts of fats, it is forced to utilize its preferred energy source.

After suffering an injury that leads to failure, the heart cannot do this on its own, so the researchers have to manipulate its metabolism to use the energy source that maximizes or maintain its function as near to “normal” as possible. “We want to provide an environment for the heart which allows it to be as effective and efficient a pump as possible, regardless of the damage it has undergone,” Dr. Chandler says.

This study was funded by the National Institutes of Health, the American Heart Association, and the Case Center for Imaging Research. Prepared by Salam Kabbani, a third-year student at Case Western Reserve University.

BATTLE CREEK, Mich., April 19, 2011 /PRNewswire/ — New research unveiled last week at the Experimental Biology conference in Washington, D.C. highlights bran as the major contributor to the health benefits associated with whole grain consumption.

The systematic review studies were presented via poster sessions and looked at the main components of whole grains – specifically the bran and fiber – to better understand the impact of each on heart health, type 2 diabetes and body weight.  The bran component is the outer layer of the grain that contains fiber, antioxidants, B vitamins, phytochemicals, and minerals like iron, copper, zinc and magnesium.

“We are excited about the results of these studies, which add to the growing body of science that supports the many benefits of bran specifically to the diet,” said Nelson Almeida, Ph.D., vice president, global chemistry, nutrition and regulatory science, Kellogg Company. “While increasing consumption of whole grains is important, this research calls out the fiber-rich bran component as potentially the most beneficial part of whole grains.”

Comprehensive literature reviews of existing science were conducted to determine what roles whole grains, specifically the fiber-rich bran component, play in reducing the risk of heart disease and type 2 diabetes and managing body weight.  Highlights include:

• A majority of prospective studies comparing bran, fiber and whole grains with the risk of heart disease showed that bran and fiber intake were more protective than whole grain intake.(1)
• Bran – particularly its fiber – appears to be a major active component in whole grains that reduce the risk of type 2 diabetes, indicating that public health messages surrounding the benefits of whole grain should emphasize the importance of bran.(2)
• Cereal fiber intake appears to have a more positive association with body weight measures than whole grain intake.  These results show many of the studies that find a link between whole grain intake and body weight are confounded by the inclusion of fiber-rich bran foods in the same category with whole grain foods studied.(3)

Support for Expanded Nutrition Advice on Whole Grain Foods Grows

The new research – supported by a grant from Kellogg Company – demonstrates the importance of fiber-rich bran to the diets of Americans, advice that is echoed by the 2010 Dietary Guidelines for Americans, which calls attention to fiber as a shortfall “nutrient of concern.” In fact, the technical report of the Dietary Guidelines highlights fiber’s compelling association with reducing the risk of type 2 diabetes and coronary heart disease, as well as fiber’s role in satiety (a feeling of fullness), which is integral to weight management.

(1) A comparison of literature on the association between intakes of bran, cereal fiber, and whole grains and risk and biomarkers of heart disease. Lu Qi, Harvard School of Public Health, Boston, MA; Susan Cho, NutraSource, Clarksville, MD; George Fahey, University of Illinois, Urbana, IL; In S Kim, National Center for Health Statistics, Hyattsville, MD; David Klurfeld, USDA ARS, Beltsville, MD.

(2) A comparison of literature on the impact of bran, cereal fiber, and whole grain intakes and risk reduction of type 2 diabetes. Susan S Cho, NutraSource, Clarksville, MD; Lu Qi, Nutrition, Harvard School of Public Health, Boston, MA; George Fahey, Animal Sciences, University of Illinois, Urbana, IL; In S Kim, National Center for Health Statistics, CDC, Hyattsville, MD; David Klurfeld, USDA ARS, Beltsville, MD.

(3) A comparison of the literature on the association between intakes of bran, cereal fiber, and whole grains and risk of adiposity measures. George C Fahey, Jr., Animal Sciences, University of Illinois, Urbana, IL; Susan S Cho, NutraSource, Clarksville, MD;  Lu Qi, Department of Nutrition, Harvard School of Public Health, Boston, MA; In S Kim, National Center for Health Statistics, Hyattsville, MD;  David M Klurfeld, USDA Agricultural Research Service, Beltsville, MD.

(4) Based on a Kellogg audit of national breakfast cereals in September 2010. The data was drawn from label, website and a syndicated database and includes nationally distributed ready-to-eat cereals from Kellogg, General Mills, Post, Quaker and Malt-O-Meal.

SOURCE Kellogg Company

NOBLESVILLE, Ind., April 20, 2011 /PRNewswire/ — Weaver Popcorn Company, Inc., is introducing the first microwave popcorn brand made with olive oil. The new Weaver Gold™ line comes in two delicious flavors – Movie Theater Butter and Parmesan with Italian Herbs & Garlic – and provides the health benefits of olive oil. The company expects to also introduce Light Butter and Classic Butter flavors in the near future.

“Since popcorn is all we make, we are continually working to add new flavors to our line and make microwave popcorn healthier,” said Mike Weaver, president and chief executive officer of Weaver Popcorn. “Movie Theater Butter is a perennial favorite flavor, but we think popcorn lovers will be especially excited about new Parmesan with Italian Herbs & Garlic. That flavor gives a gourmet twist to microwave popcorn.”

Using olive oil instead of other types of oil, like the palm oil used by many microwave popcorn brands, means that new Weaver Gold popcorn is significantly lower in saturated fat. And, both Weaver Gold flavors contain 0g trans fat per serving. Olive oil is high in monounsaturated fatty acids, and helps to protect against heart disease because it controls LDL (“bad”) cholesterol levels, while raising HDL (“good”) cholesterol levels. In addition, olive oil is high in polyphenols – a form of antioxidant.

Not only does the olive oil in Weaver Gold provide antioxidants, but popcorn itself is also a source of antioxidants. Since it is 100 percent whole grain, popcorn is also a good source of fiber.

New Weaver Gold microwave popcorn made with olive oil is now available at mass market retailers nationwide and online via Amazon.com

Vegetarians experience a 36 percent lower prevalence of metabolic syndrome than non-vegetarians, suggests new research from Loma Linda University published in the journal Diabetes Care. Because metabolic syndrome can be a precursor to heart disease, diabetes, and stroke, the findings indicate vegetarians may be at lower risk of developing these conditions.

Metabolic syndrome is defined as exhibiting at least three out of five total risk factors: high blood pressure, elevated HDL cholesterol, high glucose levels, elevated triglycerides, and an unhealthy waist circumference. The Loma Linda University study found that while 25 percent of vegetarians had metabolic syndrome, the number significantly rises to 37 percent for semi-vegetarians and 39 percent for non-vegetarians. The results hold up when adjusted for factors such as age, gender, race, physical activity, calories consumed, smoking, and alcohol intake.

“In view of the high rate of metabolic syndrome in the United States and its deleterious health effects, we wanted to examine lifestyle patterns that could be effective in the prevention and possible treatment of this disorder,” says lead researcher Nico S. Rizzo, PhD.

“I was not sure if there would be a significant difference between vegetarians and non-vegetarians, and I was surprised by just how much the numbers contrast,” he continues. “It indicates that lifestyle factors such as diet can be important in the prevention of metabolic syndrome.”

The study examined more than 700 adults randomly sampled from Loma Linda University’s Adventist Health Study 2, a long-term study of the lifestyle and health of almost 100,000 Seventh-day Adventist Christians across the United States and Canada.

Thirty-five percent of the subjects in this smaller sub-study were vegetarian. On average, the vegetarians and semi-vegetarians were three years older than non-vegetarians. Despite their slightly older age, vegetarians had lower triglycerides, glucose levels, blood pressure, waist circumference, and body mass index (BMI). Semi-vegetarians also had a significantly lower BMI and waist circumference compared to those who ate meat more regularly.

“This work again shows that diet improves many of the main cardiovascular risk factors that are part of metabolic syndrome,” says Gary Fraser, MD, PhD, principal investigator of Adventist Health Study 2. “Trending toward a plant-based diet is a sensible choice.”

Animal model finds reduced tissue damage after heart attacks following acute

WASHINGTON – Approximately one million Americans suffer a heart attack each year of which some 400,000 attacks are fatal. A key cause of heart attacks is atherosclerosis, a process in which cholesterol builds up in the arteries and impedes the ability of the blood to flow to our most vital organ. Atherosclerosis is often associated with a high-fat diet in humans, but in a new study using an animal model researchers have found that a high-fat diet for a very short period can protect the heart from heart attacks and result in less tissue damage when heart attacks occur.

Lauren Haar, Xiaoping Ren, Yong Liu, Min Jiang, Sheryl Koch, Michael Tranter, Jack Rubinstein and W.K. Jones of the University of Cincinnati (UC), Cincinnati, OH, conducted the study. Ms. Haar, a doctoral candidate, will present the team’s findings in a poster presentation entitled, “Acute high fat feeding influences cardiac function and confers cardio protection against ischemic injury,” at the meeting Experimental Biology 2011 (EB 2011). The meeting, sponsored in part by the American Society for Experimental Therapeutics (ASPET), is being held April 9-13, 2011 in Washington, DC.

Methodology

According to Haar, the researchers established test groups comprised of seven male mice. Female mice were not included in order to eliminate the effects of estrogen and metabolism of fat. Each group was fed a high-fat diet (lard-based, with 60 percent of the calories coming from saturated fat) for one of the following feeding periods: 24 hours, one-, two-, or six weeks. The control group received a standard grain and vegetable-based diet.

After the feeding periods the researchers induced ischemic injury in the hearts of the mice, similar to what humans experience during a heart attack. The animal hearts were subsequently examined for cardiac function and tissue damage.

Results: No Protection in the Longer Term

The researchers found that the injury to the heart tissue among the mice that received the high-fat diet in the short term (24 hours, one- and two-weeks) was reduced by 70 percent compared to the group that was fed the high-fat diet for six weeks which was shown to have a larger injury to the heart like the effect seen in control fed animals. No cardioprotection was observed in the six-week group, indicating that short-term “splurges” were crucial to the impact.

Further, mice fed a high-fat diet for 24 hours and then returned to a control diet for 24 hours prior to heart attack experienced a prolonged or “late phase” protection against injury, indicating that short-term high fat feeding in animal models could preserve cardiac function.

Current Study Adds to Knowledge Base

According to Haar, the study adds to an existing body of research which has found that certain patients with high cholesterol levels have better survival rates after heart injury or heart failure than do patients with lower cholesterol levels. The reason for this phenomenon is unclear.

Since few studies exist that shed light on the effect of acute high-fat diets on a heart attack, Haar and the team decided to test the impact in animals. With the current results in hand, the team will look more closely at why the cardiac protection goes away over time, and consider whether a genetic component might be involved.

Ms. Haar noted, “We hope that additional studies, which are now underway, will lead us to understand why the cardioprotective effect occurs and why it goes away over time. This understanding will provide us with better insights into the interaction between diet, health and heart diseases.”

The study was funded by the National Institutes of Heath and a UC Rehn award.

People who follow a vegan lifestyle — strict vegetarians who try to eat no meat or animal products of any kind — may increase their risk of developing blood clots and atherosclerosis or “hardening of the arteries,” which are conditions that can lead to heart attacks and stroke. That’s the conclusion of a review of dozens of articles published on the biochemistry of vegetarianism during the past 30 years. The article appears in ACS’ bi-weekly Journal of Agricultural and Food Chemistry.

Duo Li notes in the review that meat eaters are known for having a significantly higher combination of cardiovascular risk factors than vegetarians. Lower-risk vegans, however, may not be immune. Their diets tend to be lacking several key nutrients — including iron, zinc, vitamin B12, and omega-3 fatty acids. While a balanced vegetarian diet can provide enough protein, this isn’t always the case when it comes to fat and fatty acids. As a result, vegans tend to have elevated blood levels of homocysteine and decreased levels of HDL, the “good” form of cholesterol. Both are risk factors for heart disease.

It concludes that there is a strong scientific basis for vegetarians and vegans to increase their dietary omega-3 fatty acids and vitamin B12 to help contend with those risks. Good sources of omega-3s include salmon and other oily fish, walnuts and certain other nuts. Good sources of vitamin B12 include seafood, eggs, and fortified milk. Dietary supplements also can supply these nutrients.