Nadia Pietrzykowska, is a physician who is board-certified in obesity medicine and works closely with the Obesity Action Coalition, a national advocacy and awareness organization for the disease. She serves on the coalition’s education committee and writes for its publications.

Pietrzykowska’s practice in Ewing, N.J., focuses on helping people lose weight by counseling them on nutrition, exercise and lifestyle modifications. We sought her out for insights about how older adults are affected by obesity and what they can do about it.

Q: How are older adults affected any differently by obesity issues than those who are younger?

A: The way we classify obesity or being overweight can be skewed, because the Body Mass Index uses a formula to classify whether you’re of normal weight, overweight or obese, but it does not take into account body composition. That’s key for older adults because as we age we tend to lose muscle mass. You may see patients who are older who are very high in fat tissue, but it doesn’t show up on the BMI scale, and we should be tackling that fat tissue early. Secondly, being overweight causes a lot more problems for older adults than for those who are younger. When older adults have some physical disability or limitation, such as arthritis or something else, adding weight to the equation just makes it worse. The other thing is cognition. Older adults during the aging process may have cognitive function decline, and studies have shown obesity makes it worse.

Q: If someone’s already older and obese and has other chronic diseases, is it too late for losing weight to do them much good with other problems?

A: When you’re older, it does get harder because some diseases result from deterioration of organs, but it’s also been shown that reversing obesity can reverse diseases that are related — diabetes, high cholesterol, arthritis. A lot of those can be improved or reversed, and I see that a lot of times in my practice. I’ve written an article on what just losing 5 to 10 percent of your weight can do.

Q: Is there any reason it’s harder for older adults to lose weight than when they were younger?

A: When you get older, you’re more limited in the physical activity you can do. To burn one pound of fat tissue you have to run a marathon, and how many 70-year-olds do you know running marathons? If an older adult is very active and burns 100 calories a day from structured exercise, like 45 minutes on a treadmill at a moderate pace, and they do it five times in a week, that’s 500 calories for the whole week, which is about 2 or 3 ounces of weight loss per week. So physical activity by itself is not enough. You cannot outrun the fork — it’s an illusion. They have to change their food, too.

Q: Does the diet mean even more than exercise then for older adults?

A: You have to have both. If you don’t change your diet, exercise will not help you lose weight, especially in that part of the population limited in its level of physical activity. And because of older people’s tendency to lose muscle mass, it’s not only about losing calories, but making sure the right composition of proteins, carbohydrates and fats are consumed in the right proportions. Protein is linked to preserving muscle mass, so it’s important to focus on that, and it’s why it’s good to be guided by a dietitian or physician.

Q: So generally people should have some type of specialist guiding them in losing weight? What are the chances they might be successful pursuing it on their own?

A: From what I have seen in my practice, addressing it just on your own is only successful to a point. I see people do better with accountability and with structure in general. We have so much misinformation or information overload that it’s easy for people to be really lost and not sure what to listen to. And for older adults who may be on 10 different medications, just dieting can actually harm you. Let’s say you eat foods that have more greens, for example, but you’re a patient who’s on blood thinners, those greens can interact and cause trouble. When you get older physician supervision is really important.

Q: What about older adults who have made it to later years a little overweight, according to the BMI index, but not obese? If they’ve made it this far with no serious health issues, does that mean they’re OK maintaining that same extra weight, or do they need to lose some, too?

A: That’s a good question, because if you say there’s a model weight going by the BMI, that’s not always accurate. In the older population, some studies have shown a little bit of excess weight is actually protective. A BMI a little above 25 is usually fine, unless that person has multiple other medical conditions.