A long-standing common but somewhat arbitrary goal from the American Heart
Association, WHO, and other groups has been to define a diet with 30% or fewer
total calories from fat to be the definition of a low-fat diet. A group of investigators
and clinicians, including Pritikin, Ornish, Esselstyn, Connor, McDougall, Fuhrman, Barnard, Campbell, Jenkins, Greger, and Shintani advocate for a very low-fat, whole-food, or minimally processed plant-based diet with a much more restrictive definition of low-fat than the AHA.
They maintain that modest decreases in total fat in the diet will have only a modest
effect on biomarkers such as total cholesterol and LDL-C. They consider a diet to
be truly low-fat when no more than 15%, or better yet 10%, of daily calories comes
from fat. I call these diets ultra-low-fat (ULF) diets.
The investigators advocating ULF diets are likely to base their conclusions about
the health benefits of ULF plant-based diets on the clinical outcomes of small-scale
research trials among highly motivated individual patients, usually with established
CVD, who adhere closely to their restrictive diet recommendations. Although the
impacts of ULF diets on health are impressive, the evidence supporting ULF eating
is not as well supported by many large-scale, long-term epidemiologic studies or
multiple randomized controlled trials as some other dietary patterns. One reason
is that existing large-scale diet studies do not include a group of study subjects
consuming an ultra-low-fat diet because there are just not enough people eating
in this way to serve as study subjects.
Advocates of very-low-fat diets often cite the low cardiovascular and cancer disease
risk of traditional populations with vegetarian or mostly plant-based dietary
patterns, for example, the groups with low cardiovascular disease incidence in rural
China described by T. Colin Campbell in his book The China Study. Similar
diets and low risk of CVDs and cancer are found among some of the long-lived populations
featured in Blue Zone studies and Seventh Day Adventists.
Another example is found in Mexico’s Tarahumara Indians, a highly physically active group,
sometimes known as “super-runners” for their long-distance running feats. They
have been found to be essentially free from cardiovascular risk factors and free from
CVDs. Their usual diet provided less than 10% of calories from fat and consisted
of corn, beans, fruit other vegetables, and small quantities of game, fish, and eggs.
A traditional high carbohydrate low-fat Japanese dietary pattern is associated with
longevity. These diets emphasize soy products, fish, seaweeds, vegetables, fruits,
and green tea and are low in meats. An unfavorable characteristic of Japanese diets
is often high sodium from soy sauce and salt added to other foods such as fish,
likely contributing to a relatively high incidence of high blood pressure, stroke, and
some cancers. Japanese living in Okinawa have a long life expectancy and are
reputed to have the world’s longest disability-free lifespan. Their traditional daily
diet is low in calorie density, low in fat, and rich in plant-based foods. It features
about seven daily servings of green leafy and orange-yellow root vegetables, an equal number of servings of grain-based foods, many of which are whole grain, as well as soy, fruit, and seaweed. By weight, fish make up 11% of their diet and
meat, poultry, and eggs, just 3%. In addition to a healthy diet, many Okinawans are
reported to be physically active and lean even at age 100.
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, and elsewhere). Copyright 2021 by J. Joseph Speidel.