Recommendations for cancer prevention from the WCRF / AICR:
- Be as lean as possible without becoming underweight.
- Be physically active for at least 30 minutes every day. Limit sedentary habits.
- Avoid sugary drinks. Limit consumption of energy-dense foods.
- Eat more of a variety of vegetables, fruits, whole grains and legumes such as beans.
- Limit consumption of red meats (such as beef, pork and lamb) and avoid processed meats.
- If consumed at all, limit alcoholic drinks to 2 for men and 1 for women a day.
- Limit consumption of salty foods and foods processed with salt (sodium).
- Don't use supplements to protect against cancer.
American Institute for Cancer Research (AICR) and the World Cancer Research Fund (WCRF) published Food, Nutrition, Physical Activity and the Prevention of Cancer: a Global Perspective, the most comprehensive report on diet and cancer ever completed.
The Report took six years to produce, and the process was transparent, objective and comprehensive. First, the global scientific literature was searched for relevant studies. Initial searches found some half a million studies, which were soon culled to 22,000. Ultimately, over 7,000 scientific studies were deemed relevant and met the report’s rigorous criteria.
These studies were independently reviewed, compiled and presented to an Expert Panelexternal site of 21 world-renowned scientists, who judged the accumulated evidence and developed 10 Recommendations for Cancer Prevention.
The protein digestibility-corrected amino acid score (PDCAAS) has been adopted by FAO/WHO as the preferred method for the measurement of the protein value in human nutrition.
PDCAAS = Amino Acid Score x Digestibility
The method is based on comparison of the concentration of the first limiting essential amino acid in the test protein with the concentration of that amino acid in a reference (scoring) pattern. This scoring pattern is derived from the essential amino acid requirements of the preschool-age child.
Although the principle of the PDCAAS method has been widely accepted, critical questions have been raised in the scientific community:
- the validity of the preschool-age child amino acid requirement values (more than 4 times greater than the EAA requirement for an adult),
- the validity of correction for fecal instead of ileal digestibility,
- the truncation of PDCAAS values to 100%.
The reference scoring pattern was based on studies performed more than 25 years ago on a limited number of 2-year-old children recovering from malnutrition.
According to the current official recommendations, a 2-year old child needs ~ 3x higher essential-to-non-essential amino acid ratio, and needs essential amino acids in different proportions than adult. Methionine/cysteine is the limiting essential amino acids for adults, and for children it is lysine or tryptophan.
The use of fecal digestibility overestimates the nutritional value of a protein because amino acid nitrogen entering the colon is lost for protein synthesis in the body and is, at least in part, excreted in urine as ammonia.