Nutrition

Fruits and vegetables contain polyphenols that help to protect you from chronic inflammation. Chronic inflammation increases risk for certain cancers, heart disease, diabetes and Alzheimer's disease.

Whole grains are easy to cook on the stovetop, just as you would cook rice or pasta. I always cook one pound (2½ cups) of whole grains at a time, since they keep well -- refrigerated or frozen. Leftovers can be reheated in a microwave or used in salads. I make my own "instant grains" by packaging ½-1 cup portions in baggies and storing them in the freezer. They take a minute or less to thaw in the microwave.

In the last year, I have seen two experienced cyclists who suffered recurrent numbness and tingling of their hands when they rode long distances. Both had low blood levels of vitamin B12 and one was cured by taking 1000 mcg per day of vitamin B12 pills, the other by eating fish.

Eating regular meals five days a week and markedly reducing calories for the other two days may be the best way to lose weight and keep it off. This approach to weight loss is called "intermittent fasting." We have some good data on how effective this diet regimen is for animals, but we are just starting to see the results of research on humans. Most of the studies on humans do not ask participants to avoid all food on their "fast" days.

Intermittent fasting works because it causes repeated "flipping of the metabolic switch." After you have fasted for about 12 hours, you start to lose body fat because your body is forced to change temporarily from its main energy source, glucose (sugar) to fat from the fat stored in your body, and using these fatty acids that are converted to energy to produce ketones that are also used for energy.

A recent analysis of 86 studies found that "there is no association between nuts and weight gain, and in fact some analyses showed higher nut intake associated with reductions in body weight and waist circumference. The researchers from University of Toronto noted that even though nuts are concentrated sources of fats, "The physical structure of nuts may also contribute to fat malabsorption due to the fat content in nuts being contained within walled cellular structures that are incompletely masticated or digested."

In a recent study of time-restricted eating, a group of 19 people with metabolic syndrome (also called pre-diabetes) ate their usual meals but ate only between 8AM and 6PM (10 hours) and took in no calories during the other 14 hours each day.

Two companies -- Impossible Foods and Beyond Meat -- dominate the market for plant-based burgers that taste like meat. A major concern is that these products have not been tested for long-term safety.

A review of 17 different studies involving more than 560,000 people who suffered 37,000 heart attacks and strokes, followed for 10 years, found that compared to those who ate the lowest amount of fried food per week, those who ate the most suffered a 28 percent greater risk of a major heart attack or stroke, a 22 percent higher risk of heart disease, and a 37 percent higher risk of heart failure.

Intermittent fasting does not mean complete avoidance of foods and drinks. Instead, you markedly reduce your intake of food during certain periods. The benefits of intermittent fasting can be seen as long as you significantly reduce your total caloric intake during those periods.

Nuts are a rich source of fat, but many studies have shown that the fat in nuts is absorbed very poorly. This month a study explains why nuts are not fattening.

Many scientific studies show that eating sugar-rich whole fruit is healthful, even for people who are diabetic. However, I tried eating an extremely large amount of fruit (15-20 clementines or 10 regular oranges per day), and my previously normal fasting blood triglyceride level rose to levels higher than 460 mg/dL (normal is under 150). Eating that much fruit had raised my blood sugar level so high that it caused the high rise in triglycerides, which increased my risk for heart attacks.

Forty-two percent of North Americans have vitamin D levels below 20 ng/mL, which makes them deficient by most standards. Vitamin D deficiency is associated with increased risk for developing many diseases

Hundreds of studies done in the last 15 years have shown how your microbiome (gut bacteria) helps you to retain your health, and that what you eat determines the ratio of healthful to harmful types of bacteria in your colon. These bacteria govern your immune system that determines, to a large degree, what diseases you will develop and how long you will live.

When you eat a food, your blood sugar level rises. The food that raises blood sugar the highest is pure table sugar. Glycemic index is a ratio of how high a particular food raises blood sugar in comparison to how high table sugar raises blood sugar levels.

Probiotics are live bacteria and yeasts that can live in your body and help to keep you healthy. Probiotics are available in live-culture fermented foods such as yogurt, kefir (a probiotic milk drink), buttermilk, kombucha (fermented tea), tempeh, miso and natto (fermented soybean products), kimchi, sauerkraut, some pickles, and some fermented cheeses.

Amid growing concerns about artificial sweeteners, many of my readers asked whether stevia can also change gut bacteria. Stevia is a sugar substitute extracted from the leaves of a plant, Stevia rebaudiana, and is almost 200 times sweeter than regular table sugar. In 2008, the FDA declared that stevia was safe in foods and beverages.

The U.S. Preventive Services Task Force does not recommend the routine use of vitamin or mineral pills to prevent chronic diseases (USPSTF Bulletin, May 4, 2021). Heart disease is the leading causes of death in the U.S. today, but taking vitamin pills has not been shown to prevent heart disease, and neither the American Heart Association nor the American College of Cardiology recommend them.

Colon bacteria convert choline and lecithin into a chemical called TriMethylAmine (TMA), which is absorbed into your bloodstream and travels to your liver where TMA is converted to TriMethlAmine Oxide (TMAO).

At one time I followed a vegan diet and ate no animal products at all, primarily based on data that associated eating mammal meat and processed meats with increased risk for diabetes, heart attacks, certain cancers and premature death. However, a couple years ago I became very forgetful, so I got a complete evaluation for memory loss and found that my B12 level was low.

Nitrates from the foods you eat can be converted in your body to nitric oxide, which widens blood vessels to increase blood flow throughout your body, to improve exercise tolerance and to help prevent heart disease and to lower high blood pressure

If you are trying to control your weight, you should not skip breakfast because the food that you eat in the morning causes you to burn more than two and a half times as many calories as the food you eat at night.

North Americans eat far more fat than they need, primarily from the vegetable oils that are added to just about every packaged food or fast food meal you can buy, and from our tendency to cook most of our foods in fat. It is harmful to take in a lot of fats from vegetable oils because excessive fat intake can cause high insulin levels and insulin resistance, which can cause diabetes.

No drugs, supplements or potions have been shown to extend your life, in spite of the fact that the internet is full of an incredible number of fraudulent life-extension products that provide no benefits while they steal your money. However, we do have overwhelming evidence that several healthful lifestyle habits can extend how long you live and improve your quality of life in your later years.

A study from Italy found that eating a lot of processed foods is associated with increased risk for suffering a heart attack in people who have heart disease, and dying from heart disease, even if that person followed the plant-based Mediterranean diet and all the other rules for preventing and treating heart disease.

You should eat lots of unrefined whole grains because they promote the growth of healthful colon bacteria that help to prevent death and heart disease, particularly if you are overweight or have high blood sugar levels.  A study from Iran found that people who ate lots of refined grains were at increased risk for suffering blocked arteries leading to the heart, while those who ate more whole grains were at reduced risk.

The American Heart Association recommends that you eat two servings of non-fried fish twice a week to reduce your risk for congestive heart failure, heart attacks, strokes, and sudden death from heart disease.

Researchers followed 27,078 Finnish men for 31 years and found that the more dietary cholesterol and eggs a person ate, the greater the premature total death rate and death from heart attacks. They reviewed 41 other prospective studies and found the same association between dietary egg and cholesterol intake and increased total and heart attack death rates. These results are similar to those of the NIH-AARP Diet and Health Study followed 521,120 U.S. adults, average age 62.2 years, for an average of 16 years and found that eating half an egg per day was associated with increased risk for death from heart attacks, cancer, and all causes

People who ate the most whole grains were at the lowest risk for developing diabetes, according to a recent review of data from the Nurses' Health Studies and the Health Professionals Follow-Up Study.

The National Health and Nutrition Examination Survey (NHANES) found that daily consumption of starchy snacks made from flour was associated with a 50 percent increased risk of death from all causes and a 44-57 percent increased risk of death from a heart attack. This study of 21,503 North Americans, with 149,875 person-years of follow-up, also found that lunches based on refined grains were associated with a 44 percent increased risk of cardiovascular death.