This article debunks the idea presented in a pair of studies that a “high protein diet” — in particular protein from animal sources — would cause cancer.
- “Does exercise exert a protective effect?” – this study did not measure exercise.
- “What about sources of protein?” – this study did not measure anything beyond whether it came from an animal or plant. Chicken breast is not comparable to processed bologna meat.
- “Do these results apply to persons younger than 50?” – we don’t know
- “What about eating your veggies and fruits?” – vegetable and fruit servings were not counted, just carbohydrates and fats.
- “What did they eat in place of protein in the low protein group?” – protein as a percent of caloric intake was assessed, but not levels of carbs or fats (beyond group averages before division into thirds for analysis), so we don’t know if the macronutrient used to replace protein had a protective effect or not.
- “Fast food versus home cooked?” – not measured.
- “Could a healthy lifestyle completely circumvent these effects?” – perhaps, but the study never looked into ‘a healthy lifestyle’ beyond macronutrients
- “What about weight loss?” – the study controlled for ‘attempted weight loss’, so it would be prudent to assume that no significant weight loss occurred in most subjects. Due to this, any questions pertaining to whether weight loss exerted a protective effect (usually does in other studies, if the weight loss occurs in obese persons) cannot be answered by this study.