Dear Dr. Prescott,
How can thin people develop type 2 diabetes, especially if they eat well?
Jill Holmes Craighead
Although we may think of type 2 diabetes as an obesity-related illness, about 15 percent of the 26 million Americans diagnosed with the disease aren’t overweight. Many of these folks fall into a category first identified by medical researchers in the early 1980s: “metabolically obese normal weight.” I’ve also heard them referred to as TOFI—thin outside, fat inside.
The defining characteristic of TOFIs is a body that falls in the normal weight range but nevertheless displays metabolic abnormalities typically associated with obesity. These are factors like high rates of insulin resistance and triglycerides. TOFIs also tend to carry fat around the middle, which typically affects the heart and liver more than fat in the hips and thighs.
Genetics almost certainly play a role in this phenomenon, but another important factor is fitness. While most research lumps fitness and fatness together, those studies that have differentiated between the two have found that it’s healthier to be fat and fit than thin and out of shape. For example, even where regular aerobic exercise doesn’t lead to weight loss, studies have shown that it reduces fat in the
liver, where it may do the most
metabolic damage.
You can never completely eliminate your risk of type 2 diabetes. Still, to minimize your chances of developing this disease (and others), it’s not enough to eat right and watch your weight. You need to stay active, too.
Dear Dr. Prescott,
What are the odds of children having multiple sclerosis if they have a parent who has MS? And what age is it appropriate to have them tested?
Debi Camp
For this question, we brought in another Dr. P—Dr. Gabriel Pardo, director of OMRF’s Multiple Sclerosis Center of Excellence.
Let’s start by saying that the odds are very low. MS is not an inherited disorder in the classic sense, meaning that we cannot calculate the specific probability of a child having the disease if one or both of the parents have it. Nonetheless, we know that certain genes increase the susceptibility of developing MS, and we do get our genes from our parents. So how does it work?
We believe that several genes contribute to the overall risk of having MS. But other factors such as exposure to viral infections, vitamin D levels, geographical region, gender and ethnicity also come into play. Because we can’t quantify or predict all those elements, we can’t accurately estimate the risk of developing MS in a given individual. However, from studying large populations we have learned that if you have a first-degree relative (a parent or sibling) with MS, your risk of developing the disease is low—around 1 in 40.
What’s more, there currently is no definite test to diagnose MS. So diagnosis is a complicated process based on historical evidence, abnormalities on physical examination, the results of ancillary tests such as MRI and, on occasion, a spinal
fluid analysis.
The bottom line: We don’t recommend specific screening in children who have a parent with MS, unless, of course, children are starting to exhibit symptoms of the disease.
