All red meat is risky” glared the headlines of Tuesday’s LA Times. That got my attention. We eat red meat probably 6-8 times a week between lunches and dinners.
LIMITS OF EPIDEMIOLOGICAL STUDIES
First off, this is an epidemiological study. That means a group of people were asked about their eating and lifestyle habits 20 years ago and that data was compared to mortality records. There are a few reasons to question the findings.
First, association is not the same as cause and effect. No one, not the researchers nor the journalist makes this point clear. The thinking is that if you study lots of people (110,000 in this case) over a long period of time (20 years), the data has stronger statistical significance. It does. But the study design limits interpretation. An epidemiological study won’t ever be able to prove beef causes the outcomes described.
WHAT’S A FOOD FREQUENCY QUESTIONNAIRE ?
Second, people being surveyed were asked about their food habits using a food frequency questionnaire, a very limited tool. Here is what some scientists have to say:
“The substantial limitations of FFQs have been known for some time (1) and published studies based on FFQ-derived data have long included in their discussion sections a litany of weaknesses due to suboptimal dietary assessment. However, few of us expected the astonishingly poor measurement characteristics of FFQs when compared with doubly labeled water (a gold standard for energy intake)”
I find the lead author’s assertion that “there is no amount of red meat that is good for you” rather arrogant given the limitations of the study.
A VEGETARIAN DIET ISN’T NECESSARILY HEALTHY
Lastly, this study is presented as if it can stand alone, without any context of other findings. A note to the journalists: It is not enough to have Dr. Ornish offer his opinion. That is not science; it is pandering to his particular bias regarding a vegetarian diet. When people eat a plant based diet, they don’t just eat vegetables. They often eat lots of refined starch and sugar.
The thinking that people will eat more healthfully and have less chronic disease without red meat is an interesting assumption. I know many of my own clients who are healthier, leaner, with less evidence of disease from actual bio-markers like blood pressure, serum glucose levels, lipid values (cholesterol, triglycerides, etc) and body composition when they eat enough protein—including red meat— in their diet.
IS IT THE CATTLE OR WHAT WE DO TO THEM?
I do have a few reservations. There are a couple of reasons eating beef could be associated with greater risk of disease. Cattle are raised over a longer period of time than poultry. They accumulate more fat.
1. When they are fed a diet of corn, soy and stale bakery products (allowed by the USDA up to 2.5 kg. per day) their fat is higher in pro-inflammatory omega 6 fatty acids and after six months of a feedlot diet, the omega three contents drops in direct relationship to time away from the pasture. It is clear that the animal scientists who champion this feed were far more concerned with yield and quality of the product (ie: profit potential) than any nutritional ramifications.
2. Persistent organic pollutants accumulate in fat tissue. These substances are endocrine disruptors and have a very strong link to disease. Cattle have a greater body burden than other animals because of their longer lifespan and greater fat accumulation before slaughter.
So is it the beef or the way we conventionally feed cattle? Is it red meat or the fact that we spew polluting chemicals into our environment and can’t find the political will to contain the contamination?
We don’t have those answers. In the meantime, I will continue to enjoy my grass fed beef, knowing I am doing what I can to minimize what I see as the real risks to my health.