Vitamin C RDA should be doubled to reduce risk of stroke, cancer, heart disease
The recommended dietary allowance, or RDA, of vitamin C is less than half what it should be, scientists argue in a recent report, because medical experts insist on evaluating this natural, but critical nutrient in the same way they do pharmaceutical drugs and reach faulty conclusions as a result.
This is far from the only example of RDAs being set lower than the available scientific literature supports. The RDA for vitamin D is currently 600 IUs for those 1-70 years of age, however, there is substantial scientific research which indicates that an intake of up to 5000 IUs a day is more appropriate for most people.
The researchers, in Critical Reviews in Food Science and Nutrition, say there’s compelling evidence that the RDA of vitamin C should be raised to 200 milligrams per day for adults, up from its current levels in the United States of 75 milligrams for women and 90 for men.
Rather than just prevent the vitamin C deficiency disease of scurvy, they say, it’s appropriate to seek optimum levels that will saturate cells and tissues, pose no risk, and may have significant effects on public health at almost no expense – about a penny a day if taken as a dietary supplement.
Onion’s antioxidant potential may offer brain benefits
Supplementing the diet with onion and extracts from the vegetable may protect the brain from additional damage linked to stroke, suggests preliminary data from a study with mice.
According to findings published in the peer-reviewed journal Nutrition , the antioxidant potential of onion extracts was associated with higher activity of antioxidant enzymes and lower levels of in malondialdehyde (MDA – a reactive carbonyl compound and a well-established marker of oxidative stress) in brain tissue.
“The present study may provide extra motivation for the consumption of onions,” wrote researchers from Ajou University School of Medicine in South Korea.
“The results from this study suggest that onion extract may be a beneficial nutrient for the prevention of ischemic [blood-brain barrier] damage, and that the underlying mechanisms may include, at least in part, its antioxidant effects.”
Study details
The Korean researchers reduced blood flow in the brain of lab mice and then compared the effects of an onion extract with control animals. Specifically, the researchers looked at dysfunction of the blood-brain barrier, and changes in the activities of antioxidant enzymes catalase and glutathione peroxidase, and on levels of MDA.
Results showed that the content of water in the brain increased following the induced stroke, but this was reduced in onion-treated animals.
Iron Supplements Fight Fatigue
Some women with unexplained fatigue may get a bit more pep from iron supplements – even if they do not have full-blown anemia, a new clinical trial suggests.
The study focused on women who were chronically tired and had relatively low iron stores. They did not, however, have full-blown iron-deficiency anemia, in which the body has too few oxygen-carrying red blood cells.
It has not been clear whether iron supplements can help battle fatigue in non-anemic women.
To find out, Swiss researchers randomly assigned 200 women with unexplained fatigue to take either 80 milligrams of iron a day or a placebo (identical-looking pills with no active ingredient.)
Over 12 weeks, both groups improved. But women on iron supplements fared better, the researchers report in the Canadian Medical Association Journal.
On average, scores on a standard measure of fatigue fell by nearly half – from about 25 to 13, on a scale of zero to 40 – among women getting the extra iron.
That compared with a 29 percent decline in fatigue reported by the placebo group, whose average score fell from about 25 to just over 16.
Soy Reduces Inflammation
A study in this month’s Journal of the Academy of Nutrition and Dietetics shows that soy products have a marked anti-inflammatory effect. Researchers examined the diets and measures of inflammation in 1,005 middle-aged Chinese women who were part of the Shanghai Women’s Health Study. The more soy products the women consumed, the less inflammation they experienced. Inflammation is linked to cancer, type 2 diabetes, and cardiovascular disease. Possible mechanisms proposed for the reduced inflammation include the protective effects of phytoestrogens or of omega-3 fatty acid found in soy products.
‘Dessert’ with breakfast boosts weight loss
Starting your morning with a high-protein food and a “dessert” — such as a doughnut or a slice of cake — may help you lose weight and keep it off, a new study suggests.
However, several nutritionists said they weren’t ready yet to embrace the study’s conclusions.
When researchers from Tel Aviv University’s Wolfson Medical Center in Israel compared two diet regimens — one featuring a low-carbohydrate breakfast, the other a high-protein, high-carb breakfast — the sweets-with-breakfast group lost more weight after eight months.
“Although dietary restriction often results in initial weight loss, the majority of obese dieters fail to maintain their reduced weight,” wrote the study’s authors.
Diet-related weight loss often triggers hunger and cravings while decreasing suppression of ghrelin, a hormone that stimulates hunger, the researchers said. This may encourage weight gain. But, “a high protein and carbohydrate breakfast may overcome these compensatory changes and prevent obesity relapse,” they concluded.
The findings are scheduled for presentation Monday at the Endocrine Society’s annual meeting in Houston.
But at least two U.S. nutrition experts question the wisdom of encouraging regular consumption of sweet, calorie-dense, low-nutrition foods.
Juice concentrate supplement may aid childhood weight loss
A supplement made from fruit and vegetable concentrates could help boost health and fight fat in overweight children, say researchers.
The study – published in The Journal of Pediatrics – investigated the effects of supplementation with an encapsulated fruit and vegetable juice concentrate (FVJC) along with nutritional counseling on fat levels (adiposity), serum beta-carotene, retinol, and retinol binding protein-4.
The authors noted that despite public health recommendations, few children meet the daily recommended intake of fruits and vegetables. As such supplementation of essential nutrients – as an adjuvant to nutritional counseling therapy – may be of importance for the promotion children’s health and weight loss, said the US-based researchers.
Led by Dr Jose Canas, Nemours Children’s Clinic, USA, the research team revealed that supplementation with the juice concentrate was associated with an increase in serum beta-carotene concentrations, reduced abdominal adipose tissue and improved insulin resistance in overweight boys compared to the placebo group (who received just nutritional counseling).
“Although our study suggests beneficial effects of FVJC in the presence of nutritional counseling on adiposity and insulin resistance in prepubertal boys, we caution that FVJC capsules should not be considered as substitutes to the daily intake of fresh fruits and vegetables in children,†warned the researchers.
Coffee May Prevent Diabetes and Heart Disease
There’s now one more reason to get your morning fuel from coffee: it’s good for your heart, according to new research.
The study, published in an American Heart Association journal, comes from the Cardiovascular Epidemiology Research Unit at Beth Israel Deaconess Medical. Based on their findings, researchers now believe drinking two cups of coffee a day will lower the risk for diabetes, which as a result lowers the risk for heart failure.
The size of your ‘two cups of coffee’ is important, however, and shouldn’t exceed more than 8 ounces. By keeping these parameters, researchers say people may be able to lower their risk of heart failure by as much as 11 percent compared to non-coffee drinkers. But if you exceed that 16-ounce a day limit, it may actually undermine the beneficial qualities.
The first author of the study, Elizabeth Mostofsky, explained this is because “protection slowly decreases with more consumption and it seems there’s no further benefit for people who drink five or more servings a day and there may actually be potential for harm.”
How Anti-Oxidants Can Change Your Life
Antioxidants deserve more attention because they help to remove free radicals or unstable molecules, which can lead to cancer and even premature aging. They are unstable in the sense that they have an incomplete number of electrons around them, which makes them more reactive then their balanced counterparts. Humans typically produce oxygen-containing molecules, which will then try to steal electrons from other molecules. This is how the damage occurs. It looks similar to rust on a car or an apple that turns brown.
Antioxidants can stabilize these radicals and help prevent any future damage they could cause. A new study by the Department of Food Science at Louisiana State University Agricultural Center in Baton Rouge just discovered that black rice has the same antioxidant power as blueberries. Better yet, it has more fiber, less sugar, can lower cholesterol and costs less. Rice is nice!
Most people know about Vitamins A, C, E, Beta-Carotene and lycopene. Let’s take a closer look at some of the more important ones you may not have been aware were so beneficial. These could be bought for tremendously high prices or you could eat a balanced diet and get your antioxidant power from having solid nutrition.
Beta-Carotene can be found in orange foods like apricots, cantaloupe, dark greens, kale, mangoes, papaya, peppers, pumpkin, spinach, squash and sweet potatoes. It is a powerful antioxidant.
Lycopene is found in apricots, pink grapefruit, papaya, guava, tomatoes and watermelon. It can guard against aging of the skin, may prevent Cancers of the prostate and mouth, diabetes, cardiovascular disease, osteoporosis and male fertility problems.
Lutein has been touted for helping the eyes and can be ingested by consuming a diet with lots of dark, green leafy vegetables like collard greens, kale and spinach.
Raisins as Effective as Sports Chews for Fueling Workouts
If you’re active, chances are pretty good that you’ve probably encountered some form of gel, goo, or sports chew. These products are touted as a convenient way to stay fueled on a long run, ride, hike, or other endurance activity. But they’re also kind of strange. There’s just something unnatural about the taste and texture of these products.
Well here’s another great reason to go natural! A study just published in the Journal of the International Society of Sports Nutrition found that raisins are as effective as sports chews for fueling workouts.
For the study, researchers at the University of California-Davis evaluated the effects of consuming commercially available carbohydrate supplements (sports chews), natural carbohydrate supplements (raisins), and water alone during physical activity.
Study participants completed an 80 minute run followed by a 5k (3.1 mile) time trial. Participants were able to complete the time trail about one minute faster when they consumed sports chews or raisins compared to water alone.
There was no significant difference in performance for the sports chews versus the raisins – both promoted about the same level of carbohydrate oxidation.
Although the study was (predictably) funded by the California Raisin Marketing Board, raisins do seem to be a more natural, economical, and wholesome alternative to fuel prolonged physical activity.
Study unlocks cholesterol-lowering activity of blueberry
The potential cardiovascular benefits of blueberry may be related to the berries’ anthocyanins interacting with bile acids to promote cholesterol reduction, suggests data from a study with hamsters.
Dietary supplementation with 0.5 and 1% blueberry anthocyanins was associated with 37 and 66% increases in bile acid excretion, according to data published in the European Journal of Nutrition.
Researchers from The Chinese University of Hong Kong also proposed a second mechanism involving an effect on gene expression linked to enhanced excretion of sterols, with sterol excretion increased by between 24 and 30%.
The doses used in this study were equivalent to 2,500 mg of anthocyanins in a 2,000 calorie diet, which is above the 900–1,800 mg per 2,000 calories doses recommended by supplement manufacturers, said the researchers.
“In this regard, the concentration of blueberry anthocyanins used in the present study could achieve its cholesterol-lowering activity under the normal physiological conditions in humans if the data could be extrapolated to humans,†they wrote.
“In addition, such high doses used in the present study had an advantage because it could maximize the biological activity of blueberry anthocyanins so that the underlying mechanisms could be thoroughly investigated.â€
