DEAR DR. ROACH: What is the recommended daily protein allowance for older adults? I am in my 70s. — P.R.
ANSWER: The best studies recommend 1-1.2 grams of protein daily per kilogram of body weight, so if you weighed 75 kilograms (177 pounds), you should be getting 75-85 grams of protein. This is a lot less than what I have seen recommended, but the recommendations for higher numbers (2 grams per kilogram each day or more) that I often see are not based on strong data.
In cases of recovery from a serious illness, or in people who are actively building muscle, higher amounts may be of benefit. These protein needs can easily be met by any healthy style of diet, including vegan. Soy proteins, like animal, fish and dairy proteins, contain all the essential amino acids, while grains are low in lysine. Since legumes and seeds are high in lysine, combining protein sources may be important for those who follow a strict vegan diet.
DEAR DR. ROACH: I am a 67-year-old male who is relatively healthy with a significant history of coronary disease, high cholesterol and now pre-diabetes. One sibling (out of five) and my paternal grandmother were diagnosed with Type 2 diabetes. My hemoglobin A1C has been around 5.6% during the past 10 years and gradually trending upward. My most recent test one month ago was 6.0%.
During this same time frame, my fasting glucose has remained in the 90s. My doctor wants to start me on metformin to ward off diabetes, but I am reluctant to start. Should I be doing more testing before starting the medication? Would it be of value to do a continuous glucose monitor? (I’m not sure if this would be covered by Medicare.) Or should I just bite the bullet and get started on metformin? — M.T.
ANSWER: The best data we have come from the National Diabetes Prevention Program, which showed that in people who are at a high risk for developing Type 2 diabetes, both lifestyle changes and metformin were effective at reducing diabetes risk.
Intensive lifestyle changes reduced diabetes risk by 58%, while metformin reduced it by 31% compared to a placebo. A more recent trial using the GLP-1 agonist tirzepatide (Mounjaro or Zepbound) found a 93% reduction in diabetes risk. These studies were done in people whose major risk for diabetes was obesity. Unfortunately, these drugs are not often covered by insurance unless there is diagnosed diabetes.
You have an A1C level that puts you in the “prediabetes” range, which is also called “impaired glucose tolerance.” The A1C is a measure of blood sugar over the past two to three months. Since your fasting blood sugar has been in the normal range, I suspect that you have elevation in blood sugar after you eat. This is the usual pattern of Type 2 diabetes, where fasting blood sugar is preserved until the person is quite advanced.
A continuous glucose monitor can give you accurate and immediate information on how your diet and exercise affect your blood sugar. In combination with a careful log, this can be invaluable to help people adjust their regimen. However, it is only approved for Type 1 diabetics and those with Type 2 diabetes who are on insulin and have low blood sugar. Still, you can get (and pay for) one yourself. Even two weeks’ worth of data can be valuable.
Intensive lifestyle changes are highly effective at preventing diabetes and, when done the right way, can reduce the risk of heart disease. Metformin reduces diabetes risk and may help with heart disease, while GLP-1 agonists dramatically reduce diabetes risk and are proven to reduce heart disease risk. Any of these are good choices.
— 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 or send mail to 628 Virginia Dr., Orlando, FL 32803.