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A new study published in Cell Metabolism reveals that ultra-processed foods may significantly harm heart health and reproductive function in young men—even when calorie intake stays the same. An international team of researchers studied 43 men aged 20–35, who alternated between three-week diets high in ultra-processed foods and minimally processed alternatives, with a three-month break between cycles. Ultra-processed foods—such as frozen pizzas, sugary cereals, chips, packaged snacks, and soft drinks—undergo extensive industrial processing. In Canada, these products account for nearly half of the average person’s diet.

Weight and Cholesterol Worsened Despite Matched Calories

Participants followed two calorie-controlled diets: one at the maintenance level and one with surplus calories. Both versions contained equal proportions of protein, fat, and carbohydrates. However, those on ultra-processed diets gained more weight and saw their cholesterol levels rise—regardless of calorie count. Lead researcher Jessica Preston said the unexpected weight gain, even in calorie-matched groups, suggests that processed foods affect digestion and metabolism differently than whole foods. Variations in fibre, nutrient density, and metabolic response may alter how the body processes energy.

Short-Term Changes Still Trigger Inflammation

Researchers also observed a brief spike in inflammation during the unprocessed diet phase, likely due to the body adjusting to a sudden dietary shift. Despite this, the study indicates that even a short-term reduction in ultra-processed food can benefit cardiovascular health, metabolism, and fertility—especially for those who consume such foods regularly.

Processed Diets Lowered Sperm Quality and Hormones

Men on the ultra-processed diet experienced reduced sperm quality, lower motility, and decreased levels of reproductive hormones, including testosterone. Preston emphasised the importance of this data for men planning to start families, noting that male fertility often lacks attention in dietary discussions. She encouraged men to take control of their lifestyle and nutrition, underscoring that dietary changes can positively impact reproductive health.

Moderation, Not Elimination, Recommended

While the findings are significant, Preston cautioned against eliminating ultra-processed foods based on one study. She acknowledged the difficulty of avoiding such foods entirely in today’s environment but advised choosing less-processed options when possible. She concluded that food processing level is a valuable consideration when making dietary choices, and small shifts toward whole foods can support long-term health.

Source: Fox News