Exercise vs. Calorie-Cutting to Lose Weight: Is T3 the Missing Link to Success?

Recent research from the National Institutes of Health has shown that even modest calorie-cutting to lose weight affects thyroid hormone activity.  It leads to a drop in T3, the active form of thyroid hormone. While this drop is slight, researchers speculate that, over time, it could reduce your metabolism and encourage your weight to creep back up.

Other research, though, shows that exercising to lose weight has no negative impact on T3 or metabolism.  Researchers at Washington University School of Medicine, in St. Louis, studied a group of 50-to-60 year old sedentary men and women for a year. Half the group used calorie restriction to lose weight and fat; the other half used exercise. Body weight, body composition, and thyroid hormones all measured. Fat mass was reduced by 5-6 % in both groups. And T3 concentrations went down in the calorie-restricted group but not in the exercise group.

What’s this mean for you? If you are a chronic dieter, and just don’t seem to have the energy or motivation to add exercise to your routine, I would suggest you check your body temperature. (See “How are body temperatures measured” for complete instructions.) Body temperature is a good indicator of metabolism. When it is low, typically below 97.8 F., your metabolism is low, too.  Some people’s temperatures can drop even when their thyroid blood tests are completely normal. This is known as Wilson’s Temperature Syndrome. T3 is the body’s main driver of basal metabolic rate. It is possible that you have low T3 , along with low body temperature and fatigue, simply from years of calorie restriction.

In such cases, replacing the T3 to bring your body temperature back to normal may give you enough energy and motivation to begin exercising.

You can discuss T3 therapy with your doctor and we will be happy to discuss your case with your doctor.  Your doctor can call 800.420.5801.

Additional support can take the form of a healthy diet, exercise, sleep, and herbs that support optimal  thyroid and adrenal function.

Once your body temperature is back to normal, start adding exercise to your weight loss regimen. Exercise will help you lose fat and build muscle, which will increase your metabolism and help you burn calories even at rest.

References:
Agnihothri RV, Courville AB, Linderman JD, et al. Moderate weight loss is sufficient to affect thyroid hormone homeostasis and inhibit its peripheral conversion. Thyroid. 2013 Jul 31.