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.
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.
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.
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 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.
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.
Egg yolks are among the richest food sources of cholesterol, and almost 100 million North American adults have high blood cholesterol levels, signifying increased risk for heart attacks. Most of the cholesterol in your body is made by your liver and less comes from the food that you eat.
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.
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.
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.
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.
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.
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.
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.
Two new studies add to the huge body of research showing that perhaps the most important dietary recommendation is to eat lots of fiber, which is found in plants. You keep on gaining health benefits until you reach at least 25 to 29 grams of fiber per day.
The various ketogenic diets that severely restrict all carbohydrates and replace them mostly with fats are associated with increased risk for non-alcoholic fatty liver disease or NAFLD. NAFLD can lead to diabetes, heart attacks, strokes, liver cancer and other cancers.
Since bacteria in your colon eat the same food that you do, what you eat determines which types of bacteria thrive in your colon. These bacteria are a prime driver of how high your blood sugar rises after meals and how many calories you absorb from the food you eat.
North Americans almost never suffer from vitamin deficiencies, except for vitamin D, yet more than 50 percent of the population spends more than 30 billion dollars each year for vitamin pills and other nutritional supplements that they do not need. Forty-five percent of those who take vitamin pills believe that they will improve their health, but we have no good evidence that they do.
North Americans spent more than $936 million on vitamin D pills in 2017, doctors ordered more than 10 million laboratory tests for vitamin D for Medicare patients at a cost of $365 million in 2016, and 25 percent of older adults take vitamin D supplements. A Kaiser Health News investigation recently reported that the man most responsible for the obsession with vitamin D pills, Boston endocrinologist Michael Holick, has been paid hundreds of thousands of dollars by supplement and drug manufacturers, the indoor-tanning industry and commercial laboratories that run blood tests for vitamin D.
Don't believe the recent headlines suggesting that people can continue to eat their usual amounts of meat without suffering any increase in risk for illness or premature death.
The most healthful time to eat is just before or after you exercise. When you eat any source of sugar, it is used for energy and a small amount is stored in your muscles and liver. All the rest is turned into a fat called triglycerides that is stored as fat, forms plaques in your arteries and blocks insulin receptors which can cause diabetes.
A recent study in mice showed that increasing dietary protein from 15 percent to 46 percent of calories caused the mice to develop 30 percent more arterial plaques than mice on their normal-protein diet, even though they did not gain more weight.
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.