Jason Smith, a business consultant, transformed his physique in his 50s, moving from what he described as a "dad bod" to a significantly healthier state. This change led to him appearing shirtless on the cover of Men's Fitness in September 2025. Smith asserts that his transformation was achieved through natural methods, specifically by overhauling his diet, ceasing alcohol consumption, and committing to regular exercise, a claim that has drawn skepticism and accusations of using testosterone replacement therapy (TRT).
Less than a decade prior to his magazine cover, Smith, then in his late 40s, was diagnosed with high blood pressure, elevated cholesterol, and pre-diabetes, alongside a risk of developing fatty liver disease. He attributed his poor health to his lifestyle, noting, "The way I was living – how I ate and drank – was more like a college student than a father in his late-40s." He subsequently studied to become a personal trainer, focusing on aiding other middle-aged men with their health.
Smith's transformation reportedly more than doubled his testosterone levels, which were previously borderline low, solely through lifestyle changes. Experts suggest that such improvements are achievable for men who consistently modify their diet, exercise routines, and sleep patterns. Dr. Jeff Foster, a physician specializing in men's health, stated that low testosterone is often a result of poor lifestyle factors such as insufficient sleep, excess weight, inactivity, and stress, and that addressing these can naturally elevate levels.
Dr. Ashley Grossman, a consultant endocrinologist, has observed a significant increase in men seeking help for low testosterone, often after private testing. He noted that many of these men do not have a true deficiency, and TRT is not always necessary. He cautioned that TRT, when used inappropriately, can suppress natural hormone production, lead to infertility, and strain the cardiovascular system.
Testosterone, a sex hormone crucial for muscle mass, bone strength, energy, and sex drive, naturally declines with age, typically starting in the 40s. However, modern lifestyles can accelerate this decline. Factors like excess weight, poor diet, lack of exercise, chronic stress, and inadequate sleep can contribute to lower testosterone levels. Medical guidance suggests that low testosterone should be diagnosed based on consistent symptoms and after considering other potential causes, rather than solely on blood test results.
According to Dr. Channa Jayasena, an endocrinologist at Imperial College London, low testosterone in most men reflects overall poor health and fitness. He estimates that only about 2-3% of men have a clinical deficiency requiring TRT, with the remainder benefiting from lifestyle adjustments.
Weight loss, particularly reducing abdominal fat, is identified as a key factor in boosting testosterone. A 2013 review indicated a strong correlation between weight loss and increased testosterone levels, proportional to the amount of weight shed. Visceral fat, stored deep within the abdomen, is considered particularly harmful and may contribute to lower testosterone by helping convert it into estrogen. High-intensity exercises that elevate heart rate, such as running or cycling, are effective in reducing visceral fat. Improving overall aerobic fitness, rather than specific types of exercise, is considered beneficial.
Adequate sleep is also vital, with research indicating that seven to eight hours per night for men aged 41-64 is optimal. Studies have shown that even short periods of sleep deprivation can significantly reduce testosterone levels. The hormone's production is largely tied to deep sleep stages, and disruptions can weaken the signals that trigger its release.
While supplements are widely marketed, experts emphasize that foundational health habits are paramount. A balanced intake of macronutrients and overall calorie management are likely to have the most impact. Though some vitamins and minerals like vitamin D and zinc may play a supporting role, and preliminary research exists on compounds in foods like cacao, no supplement can replace a healthy lifestyle. Smith advocates for prioritizing exercise, nutrition, and sleep, stating these natural methods are effective and risk-free compared to TRT.
Managing stress is another critical component. Chronic stress elevates cortisol, a hormone that can interfere with the brain's signaling pathway to the testes, suppressing testosterone production. Prolonged stress can lead the body to prioritize survival over reproductive functions, further impacting testosterone levels, especially in individuals who also struggle with poor sleep, excess weight, or inactivity.