Morning Sunlight Exposure Key to Slowing Age-Related Weight Gain, Expert Says

WIM Clinic's Woo Chang-yoon highlights sunlight's role in hormonal balance and metabolic health for middle-aged weight management "When I was in my 20s, I could fast for a week without a problem, but now my hands shake if I skip just one meal." This is a common complaint among middle-aged office workers. Many people feel that as they age, weight gains easily and once gained, it is difficult to lose. This is not merely a matter of willpower. It results from a combination of muscle loss, hormonal changes, and ineffective dieting methods.

Woo Chang-yoon, the representative director of WIM Clinic and a former endocrinology specialist at Asan Medical Center in Seoul, appeared on the YouTube channel "Chosun Money's 'People Money Met'" produced by the Chosun Ilbo's economic department. He stated, "If you maintain muscle mass well, you won't gain as much age-related weight as you might think. The problem is that hormonal changes occur as we age, and these changes work in a way that reduces muscle." Woo, who runs the YouTube channel "Doctor Friends" with 1.42 million subscribers, recently published the book *'The Body That Doesn't Gain Weight'*. Woo analyzed that the difficulty in enduring hunger as one ages is due to changes in blood sugar regulation.

He explained, "As we get older, our 'metabolic flexibility' -- the ability to efficiently use energy -- declines." A key change is the increased fluctuation in blood sugar levels. "When young, blood sugar remains relatively stable even if a meal is skipped. However, as we age, the body reacts strongly even to minor drops in blood sugar. The body perceives this as a crisis, even if it's not actual hypoglycemia.

Stress hormones are then secreted, rapidly raising blood sugar again. This process can cause dizziness or trembling hands. This leads to seeking food again, creating a vicious cycle: eating, blood sugar rising, dropping again, and eating once more, disrupting metabolic balance." Woo emphasized, "After the age of 40, insulin hormone becomes critical. High insulin resistance creates an environment where muscle loss occurs more easily." For women, this is compounded by decreased estrogen.

He noted, "Estrogen protects muscles. When this hormone declines, the body's ability to synthesize or maintain muscle also weakens. This is why protein intake becomes much more important during this period." Exercise methods are also crucial for middle-aged individuals. Woo cautioned, "High-intensity strength training on an empty stomach should be avoided.

If you exercise in a fasted state, such as in the morning, your body lacks the materials to build muscle. Without protein supply, muscle-building efficiency drops significantly, and recovery is also hindered." Woo added, "Abdominal obesity in middle-aged men is deeply related to hormonal changes." He explained, "Male hormones decrease by about 1% annually after the age of 30. Over 20 years, this can lead to a reduction of over 20%." Sleep deprivation exacerbates the situation. "Even one week of poor sleep can significantly lower male hormone levels.

This leads to reduced muscle and increased fat, altering body composition." Woo stated, "Increased abdominal fat further disrupts hormonal balance." He elaborated, "As fat increases, male hormones convert to female hormones. This weakens the brain's signal to produce male hormones. Eventually, the body develops a physique where the stomach protrudes and weight is hard to lose." So, where should middle-aged people start their weight management? Woo suggested, "Exposing yourself to sunlight for 10-20 minutes after waking up in the morning." "Sunlight normalizes melatonin rhythms, the sleep hormone, and aids vitamin D synthesis.

Improved sleep quality restores the balance of stress and appetite-regulating hormones. This naturally stabilizes appetite." For more details, watch the "Chosun Money" video. ▶ To view the "Chosun Money" video on portals like Naver, copy and access the link below: