The Right “5-a-day” Mix is 2 Fruit and 3 Vegetable Servings for Longer Life

Studies representing nearly 2 million adults worldwide show that eating about five daily servings of fruits and vegetables, in which 2 are fruits and 3 are vegetables, is likely the optimal amount for a longer life, according to new research published today in the American Heart Association’s flagship journal Circulation.

Diets rich in fruits and vegetables help reduce risk for numerous chronic health conditions that are leading causes of death, including cardiovascular disease and cancer. Yet, only about one in 10 adults eat enough fruits or vegetables, according to the U.S. Centers for Disease Control and Prevention.

“While groups like the American Heart Association recommend four to five servings each of fruits and vegetables daily, consumers likely get inconsistent messages about what defines optimal daily intake of fruits and vegetables such as the recommended amount, and which foods to include and avoid,” said lead study author Dong D. Wang, M.D., Sc.D., an epidemiologist, nutritionist and a member of the medical faculty at Harvard Medical School and Brigham and Women’s Hospital in Boston.

Wang and colleagues analyzed data from the Nurses’ Health Study and the Health Professionals Follow-Up Study, two studies including more than 100,000 adults who were followed for up to 30 years. Both datasets included detailed dietary information repeatedly collected every two to four years. For this analysis, researchers also pooled data on fruit and vegetable intake and death from 26 studies that included about 1.9 million participants from 29 countries and territories in North and South America, Europe, Asia, Africa and Australia.

Analysis of all studies, with a composite of more than 2 million participants, revealed:

  • Intake of about five servings of fruits and vegetables daily was associated with the lowest risk of death. Eating more than five servings was not associated with additional benefit.
  • Eating about two servings daily of fruits and three servings daily of vegetables was associated with the greatest longevity.
  • Compared to those who consumed two servings of fruit and vegetables per day, participants who consumed five servings a day of fruits and vegetable had a 13% lower risk of death from all causes; a 12% lower risk of death from cardiovascular disease, including heart disease and stroke; a 10% lower risk of death from cancer; and a 35% lower risk of death from respiratory disease, such as chronic obstructive pulmonary disease (COPD).
  • Not all foods that one might consider to be fruits and vegetables offered the same benefits. For example: Starchy vegetables, such as peas and corn, fruit juices and potatoes were not associated with reduced risk of death from all causes or specific chronic diseases.
  • On the other hand, green leafy vegetables, including spinach, lettuce and kale, and fruit and vegetables rich in beta carotene and vitamin C, such as citrus fruits, berries and carrots, showed benefits.

“Our analysis in the two cohorts of U.S. men and women yielded results similar to those from 26 cohorts around the world, which supports the biological plausibility of our findings and suggests these findings can be applied to broader populations,” Wang said.

Wang said this study identifies an optimal intake level of fruits and vegetables and supports the evidence-based, succinct public health message of ‘5-a-day,’ meaning people should ideally consume five servings of fruit and vegetable each day. “This amount likely offers the most benefit in terms of prevention of major chronic disease and is a relatively achievable intake for the general public,” he said. “We also found that not all fruits and vegetables offer the same degree of benefit, even though current dietary recommendations generally treat all types of fruits and vegetables, including starchy vegetables, fruit juices and potatoes, the same.”

A limitation of the research is that it is observational, showing an association between fruit and vegetable consumption and risk of death; it does not confer a direct cause-and-effect relationship.

“The American Heart Association recommends filling at least half your plate with fruits and vegetables at each meal,” said Anne Thorndike, M.D., M.P.H., chair of the American Heart Association’s nutrition committee and an associate professor of medicine at Harvard Medical School in Boston. “This research provides strong evidence for the lifelong benefits of eating fruits and vegetables and suggests a goal amount to consume daily for ideal health. Fruits and vegetables are naturally packaged sources of nutrients that can be included in most meals and snacks, and they are essential for keeping our hearts and bodies healthy.”

Source: American Heart Association

Natural Compound in Vegetables Helps Fight Fatty Liver Disease

Paul Schattenberg wrote . . . . . . . . .

A new study led by Texas A&M AgriLife Research scientists shows how a natural compound found in many well-known and widely consumed vegetables can also be used to fight fatty liver disease.

The study demonstrates how non-alcoholic fatty liver disease, or NAFLD, can be controlled by indole, a natural compound found in gut bacteria – and in cruciferous vegetables such as cabbage, kale, cauliflower and Brussels sprouts. It also addresses how this natural compound may lead to new treatments or preventive measures for NAFLD.

The study was recently published in Hepatology and can be found on PubMed.gov.

“Based on this research, we believe healthy foods with high capacity for indole production are essential for preventing NAFLD and are beneficial for improving the health of those with it,” said Chaodong Wu, M.D., Ph.D., a Texas A&M AgriLife Research Faculty Fellow and principal investigator for the study. “This is another example where altering the diet can help prevent or treat disease and improve the well-being of the individual.”

About NAFLD and indole

NAFLD occurs when the liver becomes “marbled” with fat, sometimes due to unhealthy nutrition, such as excessive intake of saturated fats. If not properly addressed, this condition can lead to life-threatening liver disease, including cirrhosis or liver cancer.

Many diverse factors contribute to NAFLD. Fatty liver is seven to 10 times more common in people with obesity than in the general population. In addition, obesity causes inflammation in the body. Driving this inflammation are macrophages, types of white blood cells that normally battle infection. This inflammation exacerbates liver damage in those with liver disease.

Gut bacteria can also have an effect – either positive or negative — on the progression of fatty liver disease. These bacteria produce many different compounds, one of which is indole. This product of the amino acid tryptophan has been identified by clinical nutritionists and nutrition scientists as likely having preventive and therapeutic benefits to people with NAFLD.

The National Cancer Institute also notes the benefits of indole-3-carbinol found in cruciferous vegetables, including their anti-inflammatory and cancer-fighting properties.

A comprehensive and multi-level study on fatty liver disease

The present study examined the effect of indole concentrations on people, animal models and individual cells to help determine indole’s effect on liver inflammation and its potential benefits to people with NAFLD. It investigated the extent to which indole alleviates non-alcoholic fatty liver disease, incorporating previous findings on gut bacteria, intestinal inflammation and liver inflammation. It also incorporated investigation into how indole improves fatty liver in animal models.

For the study, researchers investigated the effects of indole on individuals with fatty livers. As research collaborator Qifu Li, M.D., was also a physician at Chongqing Medical University in China, the team decided he should lead the clinical research using Chinese participants.

In 137 subjects, the research team discovered people with a higher body mass index tended to have lower levels of indole in their blood. Additionally, the indole levels in those who were clinically obese were significantly lower than those who were considered lean. And in those with lower indole levels, there was also a higher amount of fat deposition in the liver.

This result will likely extend to other ethnicities, Li noted, though ethnic background may have some influence on gut bacteria populations and the exact levels of metabolites.

To further determine the impact of indole, the research team used animal models fed a low-fat diet as a control and high-fat diet to simulate the effects of NAFLD.

“The comparisons of animal models fed a low-fat diet and high-fat diet gave us a better understanding of how indole is relevant to NAFLD,” said Gianfranco Alpini, M.D., a study collaborator and former distinguished professor of Texas A&M Health Science Center, now the director of the Indiana Center for Liver Research.

Alpini said treatment of NAFLD-mimicking animal models with indole significantly decreased fat accumulation and inflammation in the liver.

The research team also studied how indole affected individual cells.

Shannon Glaser, Ph.D., a professor of Texas A&M Health Science Center, said that in addition to reducing the amount of fat in liver cells, indole also acts on cells in the intestine, which send out molecular signals that dampen inflammation.

“The link between the gut and the liver adds another layer of complexity to studies on non-alcoholic fatty liver disease, and future studies are very much needed to fully understand the role of indole,” Glaser said.

Additional nutrition research needed

“Foods with a high capacity of indole production or medicines that mimic its effects may be new therapies for treatment of NAFLD,” Wu said, adding prevention is another important aspect to consider.

“Preventing NAFLD’s development and progression may depend on nutritional approaches to ensure that gut microbes allow indole and other metabolites to function effectively,” he said. “Future research is needed to investigate how certain diets may be able to achieve this.”

Wu said in future research he hopes to collaborate with food scientists and clinical nutritionists to examine what healthy foods can alter gut microbiota and increase indole production.

Source: AgriLife Today

More Evidence Fruits and Greens Can be Good for the Brain

Lisa Rapaport wrote . . . . . . . . .

Middle-aged men who eat lots of fruits and vegetables may be lowering their odds of cognitive problems as they get on in years, compared to peers who don’t consume these foods very often, a U.S. study suggests.

Researchers followed almost 28,000 men for two decades starting when they were 51 years old, on average. Every four years, participants answered questionnaires about their consumption of fruits, vegetables and other foods. They also took tests of thinking and memory skills when they were 73 years old, on average.

Based on those test results, researchers found that by the time they were in their later 70s, men who had regularly eaten the most vegetables over the previous decades were 17 percent less likely to have moderate cognitive problems and 34 percent less likely to have more extensive cognitive deficits than men whose diets contained the least produce.

Fruit consumption, overall, didn’t appear to influence the risk of moderate cognitive problems, but men who drank more orange juice were 47 percent less likely to have extensive cognitive deficits than men who drank the least, the researchers note in the journal Neurology.

“Long-term intake of vegetables (e.g., green leafy, dark orange and red vegetables), fruit (e.g. berry fruits) and fruit juice (e.g. orange juice) may be beneficial for late-life subjective cognitive function among U.S. men,” lead study author Changzheng Yuan of the Harvard T.H. Chan School of Public Health in Boston said in an email.

Men should still go easy on the orange juice, however.

“The protective role of regular consumption of fruit juice was mainly observed among the oldest men,” Yuan said.

“Since fruit juice is usually high in calories from concentrated fruit sugars, it’s generally best to consume no more than a small glass (four to six ounces) per day,” Yuan added.

To assess the impact of eating habits in middle age on cognitive function later in life, researchers administered questionnaires designed to measure memory and reasoning skills.

Source: Reuters


Today’s Comic

Caulilini, a New Cauliflower

Florence Fabricant wrote . . . . . . .

This new vegetable has stems like broccoli and florets that are lacier than cauliflower florets.

You can see the cauliflower ancestry in Caulilini Sweet Stem Cauliflower, a new vegetable with a delicate, lacy ivory crown. Caulilini is grown by Mann Packing in Salinas, Calif., and is now in New York stores. Mild in flavor and acceptable raw, caulilini will be tender after a five-minute steam and an ice-water shock. Bathe whole clusters of the flower-topped stems in butter or marinate them in a vinaigrette. Use small clusters of the flower tops to garnish a soup, like a cold cauliflower velouté.

Source: The New York Times

How to Get Children to Eat Vegetables

Parents should not reward their children for eating greens, researchers said after discovering that youngsters who are not praised for trying vegetables are more likely to eat them eventually.

The best way to get children to eat food they do not like is simply to give them repeated exposure to it, the study found.

In tests, children repeatedly offered vegetables were more likely to eventually eat them as opposed to those given a reward.

Psychologists from Ghent University in Belgium studied 98 pre-school children on 10 vegetables that were either steamed or boiled – fennel, chicory, zucchini, mushrooms, peas, leeks, Brussels sprouts, beetroot, spinach and cauliflower.

The taste tests revealed that chicory was the least-liked vegetable among youngsters.

The children were then given a bowl of steamed chicory and told to choose how much to eat, while not sharing with other classmates.

After eight minutes, they were asked to rate the dish as “yummy”, “just OK” or “yucky” using cartoon facial expressions.

The trial went on twice a week for a month, with a follow-up taste test after eight weeks.

Children were split into three groups, with one group asked to try the bowl of chicory repeatedly with no further encouragement, while the other two groups were given rewards of stickers, a toy or verbal praise.

After the trial, 81 per cent of children who simply tried the chicory repeatedly liked it, compared with 68 per cent given a toy or sticker and 75 per cent given verbal praise.

The study team said: “All parents know how difficult it is to get children to eat their greens, with many offering rewards or treats in return for children finishing their vegetables.

“The results highlight that repeated exposure remains the best way to establish a liking of a food.”

The findings are published in the science journal Food Quality and Preference.

Source: The Telegraph