DEAR DR. ROACH: I am a 75-year-old woman who isn’t prediabetic or diabetic. My BMI is 31.2. My doctor has prescribed a trial of metformin for weight loss as an alternative to starting Ozempic or one of the other weight-loss drugs. I have lost three pounds in a month, which is a start; exercise and healthier eating is also encouraged. What are your thoughts on this new weight-loss tool and its possible long-term success? — J.H.

ANSWER: Metformin, a treatment for diabetes that works mostly by preventing the liver from making sugar, isn’t new and has been used to help people lose weight for at least 20 years. While it was first shown to help people with prediabetes or diabetes, it is also effective at helping people with normal blood sugar lose weight. However, the effectiveness is modest, with most people losing around 2-3 kilograms (about 5 pounds), which is stable as long as people continue the medicine.

I certainly agree with the changes in lifestyle. In studies, people who adhere to a healthier diet and exercise are likely to lose more weight than people who take metformin without lifestyle changes.

I’ve had occasional patients who get motivated by the success of metformin, making it easier for them to comply with the diet and exercise changes. I’ve also had people say the weight they lose with metformin makes it easier to exercise. Metformin is also moderately successful in preventing diabetes.

It is not as effective for weight loss as approved weight-loss medicines such as semaglutide (Ozempic). Some of my patients have read about metformin as an anti-aging drug based on animal data, and there are studies ongoing to see whether this is true in humans. I do not recommend its use for this purpose outside of a clinical trial.

DEAR DR. ROACH: I’m unable to find out from my health care provider’s clinic whether they offer a vaccine for the specific variant of COVID that is now said to be spreading. Do you know if there is a vaccine for this, and who is making it? J.A.

ANSWER: The Vaccines and Related Biological Products Advisory Committee at the Food and Drug Administration recommends against a new vaccine formulation this fall, so it appears that we will be using the same vaccine as last year. Fortunately the current vaccine appears to be effective against the new NB.1.8.1 variant, which is now present in all areas that are monitored by the World Health Organization.

The FDA has approved a new, more-effective Moderna vaccine, but at the time of this writing, it has not yet been approved by the Centers for Disease Control. The new vaccine gives high protection with less antigen. However, the specific variants of COVID used for the vaccine will not be updated this year.

DR. ROACH WRITES: Many readers were concerned about the advice given to a reader by his physician to use petrolatum (Vaseline) in his nose because of a condition called exogenous lipoid pneumonia. This is a very uncommon condition but can occur when large amounts of petroleum jelly are placed in the nose, especially when the person lays down to sleep and inhales it while asleep.

This condition can be avoided by only using a thin film in the nostrils and by not doing so immediately before bed so that any excess will come out of the nose. If a small amount is swallowed, this is not dangerous as it passes through the digestive system without being absorbed.

Dr. Roach regrets that he is unable to answer individual letters, but will incorporate them in the column whenever possible. Readers may email questions to ToYourGoodHealth@med.cornell.edu. (c) 2025 North America Syndicate Inc. All Rights Reserved