Insulin resistance can be minimized

DEAR DR. ROACH » What is insulin resistance and how do you prevent it?

— M.E.

DEAR READER » Insulin lowers blood sugar levels by moving the sugar into the cells that need it. Without insulin, cells starve for energy despite very high amounts of sugar in the blood.

A small amount of insulin should drop the blood sugar dramatically. In people with insulin resistance, the effect of insulin is blunted. In such people — like those with Type 2 diabetes or prediabetes — insulin blood levels are usually higher than they are in people without diabetes. This is often, but not always, in conjunction with obesity. However, there are several other causes of insulin resistance, including medications, stress, pregnancy, anti-insulin antibodies and genetic causes.

Glucocorticoids such as prednisone cause insulin resistance, and stress causes the body to release its own glucocorticoid (cortisol) as well as other hormones that oppose the action of insulin. There are many other drugs that can cause insulin resistance, predisposing people to weight gain and even overt diabetes.

Among these, beta-blockers, niacin, birth control pills and HIV medications are among the most important.

Insulin resistance may not be completely preventable, but it can be minimized. The most important way to do this is by having a normal body weight. Exercise directly reduces insulin resistance, even if body weight stays the same. This is one reason exercise is frequently recommended: It can make big improvements in health, even if a person doesn’t lose a pound.

DEAR DR. ROACH » I found my water aerobics class very helpful. Would a water aerobics class be safe during the coronavirus pandemic? Do chemicals in the water kill the virus?

— A.

DEAR READER » The primary way of spreading coronavirus is personto-person via respiratory droplets. If you are a few feet from another person, and you are both breathing heavily from exertion (or singing), then there is a high risk of transmitting the virus. Being in a pool does little or nothing to reduce that risk. Wearing a mask in the pool is impractical, so I don’t think a water aerobics class with multiple people is advisable.

Contact Dr. Roach at ToYourGoodHealth@med. cornell.edu.