Spending time in a heated environment, such as a sauna, may assist older humans, particularly women, overcome age-related obesity and insulin resistance, reveals a new study done on mice. The study demonstrates the effectiveness of heat treatments as a simple technique to promote healthy aging (1).

Health Benefits of Heat Therapy

The researchers discovered that older female mice who received a daily 30-minute whole-body heat treatment gained less weight and used insulin more efficiently, which helps manage blood sugar. The researchers also discovered the cellular pathways that were responsible for these positive outcomes.

“Compared to men, women have a higher likelihood of being obese or overweight,” stated research team leader Soonkyu Chung, Ph.D., associate professor in the Department of Nutrition at the University of Massachusetts Amherst. “This is especially true after menopause, when the body’s estrogen levels decrease. Our findings show that whole-body heat therapy could be an effective, non-invasive approach for treating menopausal weight gain and insulin resistance.

Rong Fan, a doctorate candidate advised by Chung, will present the findings at NUTRITION 2024, the American Society for Nutrition’s flagship annual meeting, which will be held in Chicago from June 29 to July 2.

Saunas Can Help Treat Menopausal Weight Gain

“Heat therapy could be a practical option for those with increased abdominal fat and a higher risk of metabolic diseases triggered by menopausal hormonal changes,” according to Fan. “It could be easily integrated into routine healthcare practices through regular sessions in saunas, heated baths or with specialized heat wraps.”

To replicate post-menopausal conditions, the ovaries of older female mice were removed. To stimulate weight gain, the mice were fed a Western diet high in fat (45% of total calories). For 12 weeks, one group of mice received 30 minutes of daily heat therapy in a heat chamber set to 40℃ (104°F), while the other group received no treatment.

Heat Therapy Minimizes Fat Accumulation

Mice given the heat treatment revealed minimal tissue damage and significantly lower lactate dehydrogenase levels, indicating less aging-related tissue damage. The therapy also significantly reduced the weight increase caused by a high-fat diet.

Compared to mice who did not receive the treatment, those who received heat therapy showed significant increases in insulin sensitivity and insulin signaling, as well as reduced fat buildup in important regions such as the liver and brown fat. While adipose tissue stores energy, brown fat is a metabolically active kind of fat that helps the body burn more calories. Research has revealed that when people age and reach menopause, they lose brown fat, which contributes to a slower metabolism.

Why Heat Therapy Causes More Fat Burn?

The researchers also looked into the molecular mechanisms that underpin the positive effects of heat therapy. They discovered that heat activates many chemical mechanisms, allowing the body to use energy more efficiently and burn fat. A critical role is the protein TRPV1, which acts as a calcium ion channel in the cell membrane. When activated by heat, TRPV1 initiates a process known as futile calcium cycling, in which the body expends energy (in the form of ATP) to pump calcium ions across cell membranes. This mechanism helps the body burn more energy.

TRPV1 activation, followed by calcium cycling, stimulates fat breakdown and burning. This lowers fat buildup in organs such as the liver and improves insulin sensitivity, which is important for general metabolic health. “This series of events suggests that regular application of heat can mimic the effects of calorie burning and fat loss,” according to Fan. “It could be particularly advantageous for individuals who find physical activities challenging, providing a relaxing way to improve metabolic health.”

The researchers emphasize the need for additional research to discover the ideal length and intensity of heat exposure in people for health benefits, as well as to confirm its safety and effectiveness across varied groups.

References:

1. Daily sauna time might help prevent menopause-related weight gain
   (https://www.eurekalert.org/news-releases/1048831)

Source-Medindia