The "Pitfalls" of High-Protein Foods—A Guide to Managing Heart Disease and Cancer Risks

With the trend of strength training and dieting, "high protein at all costs" has become a catchphrase. However, the source of protein and the method of preparation can influence the risk of heart disease and cancer. The World Health Organization (IARC) classifies processed meat as carcinogenic (Group 1) and red meat as probably carcinogenic (Group 2A), reporting that consuming 50g/day of processed meat increases the risk of colorectal cancer by about 18%. Grilling directly and charring increase substances like HCA and PAH, which can damage DNA. Additionally, TMAO, a compound metabolized by gut bacteria from components abundant in red meat and eggs, is associated with cardiovascular disease risk (dietary fiber may help suppress TMAO elevation). On the other hand, soy, legumes, fish, and nuts contribute to reducing cardiovascular risk. Dairy products are not universally "bad," with recent data suggesting they are generally neutral to protective. According to the Ministry of Health, Labour and Welfare's dietary intake standards (2025 edition), the maintenance requirement is 0.66g/kg body weight/day, with recommended daily intake for adults being 65g for men and 50g for women. Avoiding processed meat, limiting red meat to about 350g per week, cooking at low temperatures with marination, and shifting towards plant-based proteins and fish is the smart approach to "high protein" for Japanese people.