Archive for November, 2011

Putting Fish Oil To The Test

Tuesday, November 22nd, 2011

Studies on fish and fish oil (omega-3) supplements regularly make news. Often the results are encouraging—but not always.

Most of these were large well-designed clinical trials, which are few and far between in the world of dietary supplements.

• Heart disease: In a Dutch study of people who had already had a heart attack, omega-3 fish oil supplements did not reduce the risk of cardiovascular events over a 40-month period. This conflicts with some prior studies that did find a protective effect, and with advice from the American Heart Association that heart attack patients should take omega-3s. But unlike the older research, this New England Journal of Medicine study included mainly people on “state-of-the-art” medication, such as statins and blood pressure drugs, which could help explain the lack of effect of the supplements.

• Atrial fibrillation: In a study of people with this heart rhythm abnormality, high-dose omega-3 fish oil supplements did not reduce the risk of recurrence over a six-month period. It has been theorized that one way omega-3s from fish or supplements may reduce the risk of cardiovascular disease is by preventing heart rhythm problems, and some previous studies have suggested this. This study, in the Journal of the American Medical Association (JAMA), was the largest clinical trial to test this theory.

• Pregnancy: Though pregnant women are often advised to take omega-3 supplements (DHA, in particular, the main omega-3 fat in the brain) to boost their children’s mental development and prevent postpartum depression, DHA capsules have neither effect, according to a large Australian clinical trial in JAMA.

• Alzheimer’s disease: Omega-3 fish oil supplements do not help slow the progression of the disease, according to a study (also in JAMA) of Alzheimer’s patients in Oregon, who took either DHA or a placebo for 18 months. Some previous observational studies suggested that high intakes of DHA can help prevent or slow dementia, including Alzheimer’s.

• Cognitive decline: In contrast, another placebo-controlled study, in Alzheimer’s & Dementia, found that DHA supple­ments, taken for 24 weeks, helped improve memory and brain function in people over 55 with mild cognitive impairment. This suggests that, to help the brain, the supplements need to be started early, before mental decline progresses too much.

• Gum disease: A Harvard study in the Journal of the American Dietetic Association found that people who consumed moderate amounts of fish oil omega-3s had a lower risk of developing periodontitis, an inflammatory disease that causes gum recession and tooth loss. Omega-3s have anti-inflammatory effects.

KEEP YOUR BODY POWERFUL WITH POTASSIUM

Friday, November 11th, 2011

 

According to the U.S. National Library of Medicine (NLM) and the National Institutes of Health (NIH), potassium is a very important mineral in the human body. It is involved in both electrical and cellular functions, and is necessary for healthy heart activity, proper carbohydrate metabolism, building muscle and much more. Here are some potassium-rich foods that you can easily add to your diet:

Vegetables. Healthy amounts of potassium can be found in broccoli, peas, winter squashes, potatoes (especially the skins), sweet potatoes and lima beans. The United States Department of Agriculture (USDA) notes that eating potassium-rich vegetables may lower blood pressure, reduce the risk of developing kidney stones and decrease bone loss.
Fruits.Not only is fruit delicious, it gives your body important doses of potassium. Try citrus fruits, bananas, prunes, kiwi and cantaloupe. Interestingly, dried apricots contain more potassium than fresh apricots, and they make great snacks at school, work or on the go.
Milk and yogurt. The United States Department of Agriculture (USDA) lists an eight-ounce container of plain, non-fat yogurt as having 579 mg of potassium and only 127 calories. One cup of non-fat milk has 83 calories and 382 mg of potassium. Both are what the NLM and NIH describe as “excellent sources” of potassium.
Nuts and seeds. According to the Mayo Clinic, nuts are good sources of potassium and they contain valuable magnesium, fiber, protein and healthy fats. Almonds and sunflower seeds both offer good amounts of potassium.

It’s important to note that the human body can have too much (hyperkalemia) or too little (hypokalemia) potassium. These imbalances can be caused by a variety of diseases, medications, conditions and more, so talk to your doctor before increasing your potassium levels or drastically changing your diet in any way. For more information about potassium and other nutrients, visit the USDA at www.choosemyplate.gov.

COFFEE-CHOLESTEROL CONNECTION

Friday, November 4th, 2011

If you have high cholesterol, could your morning cup of Joe be at least partly to blame? Maybe, depending on how your coffee is brewed and how much you drink.

Most research has found that coffee drinking in general does not increase blood cholesterol or cardiovascular risk. But since the mid-1980s, studies have consistently linked unfiltered coffee to increases in cholesterol. Much of the evidence comes from Scandinavia, where coffee typically is made by boiling the grounds in hot water and is not filtered.

What’s in your cup of coffee?

Diterpene compounds in coffee beans—notably cafestol—are responsible for the cholesterol-raising effect. The longer the coffee grounds come in contact with the brewing water, and the hotter the water, the greater the amount of diterpenes released. Scandinavian-style boiled coffee has the most diterpenes, studies have shown—followed by Turkish/Greek coffee, French-press (cafetière or plunger-pot) coffee and then espresso. American-style “drip” coffee has virtually none because the paper filters trap the compounds. Percolated and instant coffees also have negligible amounts. Decaffeinating coffee does not reduce diterpenes.

Still, it takes a fair amount of unfiltered coffee to have a significant effect on cholesterol. Daily consumption of 10 milligrams of cafestol—the amount in about four 5-ounce cups of French-press coffee—has been shown to raise cholesterol by 8 to 10 percent in four weeks, mostly due to increased LDL (“bad”) cholesterol. Some people are affected more than others, and the effects may be greater in those who have higher cholesterol to begin with.

The sunny side of coffee

All coffee, no matter how it’s brewed, contains a complex mix of phytochemicals, many of which are potentially beneficial. In fact, coffee is the No. 1 source of antioxidants in the U.S. diet, because we drink so much of it. Coffee has been shown to guard against oxidation of LDL cholesterol, which makes LDL less harmful. And it’s been linked to reduced risk of diabetes, Parkinson’s disease and some other disorders. Cafestol may even have anti-cancer properties, at least in lab studies.

Bottoms up

An occasional cup of unfiltered coffee won’t raise your cholesterol significantly, if at all. But you may be consuming more unfiltered coffee than you realize because many coffee drinks—cappuccinos or lattes, for instance—are made with espresso, sometimes more than one shot. If your cholesterol is high, you might want to limit espresso to one or two a day and not go overboard with French-press coffee.