Because cancer risk varies substantially between countries and groups of people
with different dietary patterns, there have been many studies looking for links between
diet and cancer. There are many over-the-top claims that “superfoods” with
high levels of phytochemicals (a wide variety of chemical compounds that occur
naturally in plants) and antioxidants are “cancer fighters,” but much of the evidence
linking food and cancer is not particularly strong. Many retrospective studies
suggest that high fat and red meat in diets are factors that increase the risk of cancer
and that consumption of fruits, dietary fiber, vegetables, and especially the phytochemicals
in fruits and vegetables, all contribute to reduced risk.

Soy, fruits and vegetables
There is some evidence that eating traditional soy foods such as tofu may lower
the risk of cancers of the breast, prostate, or endometrium (lining of the uterus),
and possibly other cancers. For example, a study suggests that plant-derived dietary
phytoestrogens (compounds with weak estrogen-like activity found in peas,
beans, soy products, and other foods) may decrease lung cancer risk.85 And there is
some but not particularly strong evidence suggests eating fruits and vegetables may
somewhat lower the risk for cancers of the lung, mouth, throat (pharynx), larynx,
esophagus, stomach, colon, and rectum. Unfortunately, the retrospective studies
linking diet and cancer have methodological problems because of the difficulty in
accurately recalling diets, and because over many years, people frequently change
their diets.

A prospective study considered four nutritional scores and overall, breast, prostate,
and colorectal cancer risk.88 The scores are the cancer-specific World Cancer
Research Fund/American Institute for Cancer Research (WCRF/AICR) score, the
Alternate Healthy Eating Index 2010 (AHEI-2010), a score based on adherence to
the Mediterranean diet (MEDI-LITE), and the French National Nutrition Health
Program-Guideline Score (PNNS-GS). A one-point increment of the WCRF/AICR
score was significantly associated with a 12% decrease in overall cancer risk. The
three other diets were associated with smaller reductions in overall cancer risk. The
WCRF/AICR score performed best. Probably, because compared with other tested
diet scores, it included a stronger penalty for alcohol, which is a major risk factor
for several cancer sites.

A study based on the diet questionnaires submitted every four years by participants
in the Nurses’ Health Study (88,301 women, starting in 1980) and the Nurses’
Health Study II (93,844 women, starting in 1991) found that women who ate more
than 5.5 servings of fruits and vegetables each day had an 11% lower risk of breast
cancer than those who ate 2.5 or fewer servings. The study defined a serving as
one cup of raw leafy vegetables, half a cup of raw or cooked vegetables, or half a
cup of chopped or cooked fruits.

This blog presents opinions and ideas and is intended to provide helpful general information. I am not engaged in rendering advice or services to the individual reader. The ideas, procedures and suggestions in that are presented are not in any way a substitute for the advice and care of the reader’s own physician or other medical professional based on the reader’s own individual conditions, symptoms or concerns. If the reader needs personal medical, health, dietary, exercise or other assistance or advice the reader should consult a physician and/or other qualified health professionals. The author specifically disclaims all responsibility for any injury, damage or loss that the reader may incur as a direct or indirect consequence of following any directions or suggestions given in this blog or participating in any programs described in this blog or in the book, The Building Blocks of Health––How to Optimize Your Health with a Lifestyle Checklist (available in print or downloaded at Amazon, Apple, Barnes and Noble and elsewhere). Copyright 2021 by J. Joseph Speidel