Just a few ounces of nuts is all it takes to improve glycemic control and exert beneficial effects on cardiovascular and other markers of health. The protective effects on metabolism could be explained by the ability of nuts to regulate inflammation and oxidation.
The last two decades have seen a proliferation of evidence linking tree nutconsumption with a range of health outcomes. Almonds, Brazil nuts, cashews, hazelnuts, macadamias, pecans, pine nuts, pistachios and walnuts are all examples of tree nuts.
Improve Glycemic Control
A recent review of 12 clinical trials found that daily intake of tree nuts improve glycemic control in adults with type 2 diabetes.
A group of researchers analyzed the results of 12 randomized controlled dietary trials to determine the effect of nuts on four markers including fasting glucose and fasting insulinin 450 predominantly middle-aged adults in a "first-of-its-kind" systemic review.
Improved glycemic control may relate to carb displacement with tree nuts.
Fat intake, especially monounsaturated fatty acid (MUFA), has been liberalized in diabetic diets to preserve HDL cholesterol and improve glycemic control. Two ounces of nuts daily as a replacement for carbohydrate foods improved both glycemic control and serum lipids in type 2 diabetes.
Epidemiologic studies have shown that nuts may lower the risk of diabetes incidence in women.
Compared with a low-fat diet, a Mediterranean diet enriched with nuts has been found to be beneficial for Metabolic Syndrome management.
The ability of tree nuts to improve glycemic control may relate to a carbohydrate displacement mechanism by which tree nuts reduce the glycemic load of the diet by displacing high glycemic-index carbohydrates, according to the review.
Lower All-Cause Mortality Rates
A recent large pooled analysis of two of the Harvard cohorts and a recent meta-analysis of prospective cohort studies also tied daily nut consumption to lower all-cause mortality rates. Recent evidence that tree nuts lower cholesterol also resulted in an FDA-qualified health claim and their inclusion in heart association guidelines for cardiovascular risk reduction.
Nuts Decrease Cancer Risk By More Than One-Third
The data, from a large-scale prospective study, investigated the association between nut consumption and risk of pancreatic cancer in more than 75,000 women who took part in the Nurses' Health Study, and had no previous history of cancer.
"Frequent nut consumption is inversely associated with risk of pancreatic cancer in this large prospective cohort of women, independent of other potential risk factors for pancreatic cancer," explained the research team - led by Dr Ying Bao of Brigham and Women's Hospital and Harvard Medical School and published in the British Journal of Cancer.
Boost Semen Quality
Led by Dr Wendie Robbins at the University of California, Los Angeles, USA, a research team revealed that eating 75 grams of walnuts a day improves the vitality, motility, and morphology of sperm in healthy men aged 21 to 35. The study was published in Biology of Reproduction.
It's Time To Give Nuts A Prominent Place On The Food Pyramid
Given all this evidence, many researchers now think that nuts should be moved to a more prominent place on the government's food pyramid. In other words, small amounts should be part of your daily diet.
There are many substances in nuts that may explain their heart-healthy potential (and other health benefits). Nuts are rich in monounsaturated and polyunsaturated fats: these can benefit overall metabolic processes, especially when substituted for foods such as meats or cheeses which many people have problems digesting.
- folate and other B vitamins: these may reduce the risk of heart disease by lowering blood levels of homocysteine.
- copper, potassium, and magnesium--all three linked to heart health--and other minerals.
- vitamin E, possibly cardio-protective.
- arginine, an amino acid that helps relax blood vessels and inhibits blood clotting. - fiber, with all its health benefits.
- phytochemicals (notably sterols, ellagic acid, polyphenols, and saponins) that may act as antioxidants and lower cholesterol.
Which Nut Is Best
All nuts have a lot in common. Most have 160 to 190 calories and 14 to 19 grams of fat per ounce; at least three-quarters of the calories come from fat. They are also among the best plant sources of protein. There are some nutritional differences. Walnuts are richest in heart-healthy alpha-linolenic acid (an omega-3 fatty acid similar to those in fish); almonds are richest in calcium and vitamin E; brazil nuts are the best dietary source of selenium. Macadamia nuts have the most calories and fat; chestnuts the least (just 70 calories and 1 gram of fat). And peanuts are not true nuts, but legumes (like dried beans). Similar nutritionally to nuts, peanuts contain some resveratrol, a beneficial compound found in grapes.
Stick To Raw and Unprocessed
Nuts tend to be satisfying and, according to some studies, help reduce hunger longer than many foods. But only if you eat them without sugar or salt coatings which can have the opposite effect. Roasted and processed nuts destroy much of the nutritional content so stick with raw nuts when possible.
An ounce or two a day will do. Instead of using nuts as a snack, when you might eat large amounts, use them as part of a meal. Chopped nuts are tasty in fruit or vegetable salads, yogurt, oatmeal and breakfast cereals. When possible, substitute nuts for foods rich in saturated fat. Organic raw peanut butter, for instance, is definitely a healthier choice for a sandwich than cheese or most meats.
And spread the news: Raw nut butters have the same nutritional advantages as nuts.