Question: I'm an 81-year-old man, 6-feet-1-inch tall and weigh 137 pounds. Twenty years ago, my ideal weight was 160 pounds. The weight loss has occurred over the past eight years, and I'm concerned. I have an appetite, but just cannot maintain my weight. What should I do?

Answer: Staying at a healthy weight is important as you age. So being concerned about unexplained weight loss is appropriate. Although much attention is understandably focused on the health problems that come from weighing too much, not weighing enough can put you at risk for a variety of health conditions, too. Losing weight, especially if you're not trying to, could be a symptom of an underlying health issue. It's essential you get a thorough checkup with your health care provider to investigate your weight loss.

Health care providers often use body mass index, or BMI, to see if a person is at a healthy weight. BMI is a formula that uses your weight and height to estimate body fat. In general, a BMI of about 19 to 24 is considered to be within the normal range. Using your description, your BMI is 18.1, which falls in the underweight category.

Latest Video

Work with your health care provider to find the cause of your weight loss. A comprehensive physical exam is a good place to start. Health issues such as dental concerns, mood changes and swallowing problems can have an impact on the kind of foods you eat and how much you eat. In addition, some serious health problems such as heart disease, cancer and depression can lead to weight loss. If your doctor suspects an underlying medical issue could be to blame, you may need additional evaluation to confirm a diagnosis.

Review with your health care provider all of the medications you're taking. A variety of medications can cause weight loss. Certain medications may lead to a loss of taste and smell, too. That can take some of the pleasure out of eating and cause you to cut back on the amount you eat without realizing it.

As a result of your checkup, you may find the weight loss is not connected to a health concern. Instead, it may be related to lifestyle issues that are making it hard for you to get the nutrition you need. If that's the case, there are several things to consider.

First, make sure you consistently have easy access to healthy foods. If you can't go to the grocery store regularly, or if cost is a concern, consider a program such as Meals on Wheels or other dining options for seniors available in your community. Ask your doctor or another member of your health care team for information about community resources that can help.

Second, rather than having three large meals per day, try eating smaller meals more often. This can make it easier to eat more and get the nutrition you need. Eating this way also may help you avoid bothersome conditions, such as heartburn or stomach upset, that make eating less enjoyable.

Third, if your weight loss continues, consider adding nutritional supplements to your diet, such as a protein powder in milk, to help increase the number of calories you take in each day. Nutritional supplement drinks, such as instant breakfast mixes and canned or powdered shakes, also can provide a significant number of calories.

Before you start using a supplement, though, talk to a dietitian. He or she can help you find the supplements that are right for you. A dietitian also can help you make good food choices that fit your individual situation. Ask your health care provider to put you in touch with a dietitian in your area.

To submit a question, write to:

Welcome to the discussion.

Keep it Clean. Please avoid obscene, vulgar, lewd, racist or sexually-oriented language.
Don't Threaten. Threats of harming another person will not be tolerated.
Be Truthful. Don't knowingly lie about anyone or anything.
Be Nice. No racism, sexism or any sort of -ism that is degrading to another person.
Be Proactive. Use the 'Report' link on each comment to let us know of abusive posts.
Share with Us. We'd love to hear eyewitness accounts, the history behind an article.