"A boxer's diet should be low in fat and high in proteins and sugar. Therefore you should eat plenty of lean meat, milk, leafy vegetables, and fresh fruit and ice cream for sugar"

Gene Tunney recommends that boxers follow a diet low in fat, but rich in proteins and sugar. His emphasis on lean meat and milk suggests he values high-quality protein sources that support muscle repair and strength without adding excessive fat. Lean meats such as poultry, fish, or trimmed beef are particularly useful for athletes due to their amino acid content and relatively low fat. Milk, likewise, offers both protein and calcium, supporting bone health and recovery.

He also highlights the importance of leafy vegetables, which are loaded with vitamins, minerals, and fiber, all essential for maintaining general health, good digestion, and aiding physical performance. Fresh fruit is suggested as a valuable part of the diet, providing not just natural sugars, vital for quick energy replenishment, but also fiber, antioxidants, and a spectrum of micronutrients. By including fruit, Tunney acknowledges the need for carbohydrates as energy fuel, especially during intense training.

Interestingly, he singles out ice cream as a good source of sugar. At the time, nutrition science was less developed and less wary of added sugars than today. High-sugar snacks such as ice cream were believed to quickly boost energy stores, vital for grueling rounds in the ring. Sugar, easily digested, would offer short bursts of energy which could be useful in boxing matches or during tough training sessions. The inclusion of ice cream also points to the need for some dietary enjoyment, making the regimen more sustainable and psychologically satisfying.

Tunney’s dietary advice reflects the nutritional beliefs of his era, focusing on muscle-supporting proteins and energy-restoring sugars, while minimizing fats, which were often seen as unnecessary or unhealthy. His recommendations, rooted in practicality, seek a balance between strength, endurance, and agility, tailored for the demanding lifestyle of a boxer.