Nutrition Archive

Research we're watching

A plant-focused diet long touted for its ability to lower blood pressure may also help prevent heart failure, according to a new study.

The DASH diet, which stands for Dietary Approaches to Stop Hypertension, emphasizes fruits, vegetables, whole grains, low-fat dairy products, poultry, fish, and nuts while minimizing salt, sugar, and red meat consumption.

Q. I keep reading that peanut butter is a healthy food. But it contains saturated fat and has more sodium than potassium. That doesn't sound healthy to me. Is peanut butter good for you?

A. The presence of saturated fat doesn't automatically kick a food into the "unhealthy" camp. Olive oil, wheat germ, and even tofu — all "healthy" foods — have some saturated fat. It's the whole package of nutrients, not just one or two, that determines how good a particular food is for health.

There's no mercury to worry about, and flaxseed oil  does contain omega-3 fats...but not the best kind.

Troll the medical literature, and you'll come up with study after study showing that fish and fish oil are good for us, especially for our hearts but maybe also for our moods and immune systems. Various epidemiologic investigations have found that people who eat fish regularly are less likely to have heart attacks, suffer strokes, or die from sudden cardiac arrest. The definition of "regularly" varies, but it usually means at least a couple of times a week, although eating fish even once a month has been shown to make a difference.

Fish, and especially fish oil, have also been the subject of dozens of randomized clinical trials, most involving people with existing heart conditions. In large amounts (several grams a day), fish oil has been shown to nudge various cardiac risk factors ("good" HDL cholesterol, triglycerides, blood pressure) in the right direction.

Potassium is necessary for the normal functioning of all cells. It regulates the heartbeat, ensures proper function of the muscles and nerves, and is vital for synthesizing protein and metabolizing carbohydrates.

Thousands of years ago, when humans roamed the earth gathering and hunting, potassium was abundant in the diet, while sodium was scarce. The so-called Paleolithic diet delivered about 16 times more potassium than sodium. Today, most Americans get barely half of the recommended amount of potassium in their diets. The average American diet contains about twice as much sodium as potassium, because of the preponderance of salt hidden in processed or prepared foods, not to mention the dearth of potassium in those foods. This imbalance, which is at odds with how humans evolved, is thought to be a major contributor to high blood pressure, which affects one in three American adults.

Stop aiming for a particular amount of servings in each food category and focus on total daily intake.

Trying to hit the mark on a healthy diet can be challenging. You need to eat enough of the right foods to meet your body's vitamin and mineral needs.

Experts have tried to guide us over the years by recommending goals of daily food servings — such as five to eight servings of fruits and vegetables per day. But your idea of serving sizes may differ from someone else's. That's led to confusion and, now, change.

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As we've reported before, free medically tailored meals are making a big difference for older adults who have chronic illness or are recovering from a hospital stay. The meals are provided by nonprofit agencies and are customized to your dietary needs — like a potassium-controlled diet if you have kidney disease, or a diet low in vitamin K if you're taking a blood thinner. Now an observational study published online April 22, 2019, by JAMA Network Open suggests that taking part in a free medically tailored meal program is linked to fewer admissions to hospitals and nursing homes, as well as lower medical costs. Researchers looked at about 1,000 adults with health problems such as cancer or diabetes. Half took part in a free medically tailored meal program for about a year; the other half did not. During a two-year follow-up, people who received medically tailored meals had 49% fewer hospital admissions and 72% fewer nursing home admissions than those who did not receive meals. Getting the meals was also tied to a 16% reduction in medical costs each month. To find a program near you, check out the partner section of the Food Is Medicine Coalition (www.fimcoalition.org/partners).

Image: © FredFroese/Getty Images

Advice about eating eggs has evolved over the years. Should you go easy on this popular protein source?

Over the years, eggs have taken a bit of a beating, starting in the late 1960s. That's when the American Heart Association advised people to cut back on cholesterol in their diets and to eat no more than three whole eggs a week.

Decades later, eggs got a break after studies suggested that for most people, an egg a day was A-OK for heart health. But a recent report cracked down on eggs once again, suggesting that we return to the yolk-rationed days of yore (see "No yolk: Eggs linked to slightly higher risk of heart disease").

Mung beans are popular in many Asian cuisines, where they're used in soups, curries, savory pancakes, and even desserts. These small, olive-green beans have a white speck at the center. Some say the mild flavor of mung beans is reminiscent of potatoes.

Natural food stores and some conventional grocery stores may carry dried mung beans, either packaged or in bulk bins. But Americans are probably more familiar with mung bean sprouts, which are used in Chinese and Thai stir-fries. You can often find these slender, crunchy white sprouts in the produce section of your supermarket. Studies show that mung bean sprouts contain slightly higher levels of beneficial antioxidants than the unsprouted beans.

Research we're watching

Eating healthy, plant-based proteins such as beans and nuts instead of red meat may lower your odds of heart disease, new research finds.

Researchers analyzed data from 36 trials that involved more than 1,800 people to see how different diets affect cholesterol, blood pressure, and other heart disease risk factors. When they compared diets with red meat to all other types of diets combined, there weren't any notable differences in cholesterol or blood pressure (although red-meat diets did lead to high levels of triglycerides, a type of fat in the blood).

You may need more of them in your daily diet than you think.

The saying goes that good things come in small packages, and that is especially true when it comes to nutrition.

There are two major classes of nutrients in food: macronutrients and micronutrients. Macro means big, and macronutrients take their name from the fact they make up the bulk of the nutrition in the food: carbohydrates, protein, and fat. These nutrients supply your calories and serve as the building blocks for muscles and tissues. Most people get plenty — and sometimes too many — from a regular diet.