It’s been months since the conclusions of a Harvard study in epidemiology first hit the mainstream media on March 12, 2012. I believe most of the dust has settled resulting from the controversy this work created. It was conducted by members of the Harvard School of Public Health and published in the Archives of Internal Medicine:
The purpose of this study was to discover the relationship between red meat consumption and mortality. Basically, it observed the diets of approximately 140,000 men and women for up to 28 years. Summarizing, the results were as follows:
“Red meat consumption is associated with an increased risk of total Cardio-vascular disease and cancer mortality. Substitution of other healthy protein sources for red meat is associated with a lower mortality risk”
Now, in this study all of the red meat consumed was either qualified as unprocessed – beef, pork, or lamb or processed, which included: bacon, hot dogs, sausage, salami, bologna, and other processed meats. Specifically:
“In these two large prospective cohorts of US men and women, we found that a higher intake of red meat was associated with a significantly elevated risk of total, cardiovascular disease and cancer mortality, and this association was observed for unprocessed and processed red meat, with a relatively greater risk for processed red meat.”
As one would expect, the fine folks at Harvard took into account all of the covariates, such as age, body mass index, smoking, physical activity, congenital or family history of disease, illnesses, etc. They also provided the expected, requisite explanation of all the statistics and other data.
This study caused an uproar with high protein diet advocates and experts. Much of the vitriolic criticism directed at this study came from the “Atkins” and ketogenic dietary camps. Some of it came from those who respect and follow a Paleolithic or human evolutionary dietary philosophy. Being a dedicated practitioner of Paleolithic eating, I fully understood this dissention. I have since read many of the stormy, critical comments from very intelligent, scientific people.
What surprised me the most about the harsh critiques of this study was that they primarily dwelled on the following points of contention:
- This was an “observational” study, and as such was inherently flawed. That is, a hypothesis may not be tested scientifically through observation alone.
- The subjects in the study likely did not answer their questions honestly all of the time.
- It would be very unlikely that the subjects of the study could accurately remember all of the food they had consumed when recording this at a later time.
- Scientific studies are often misrepresented by the researchers who conduct them.
- The red meat definition included both processed and unprocessed versions, and the unprocessed versions are likely far worse; misrepresenting the accuracy of the final conclusion.
- Meat eating could be a marker for those adopting other less healthy lifestyle habits which would also likely increase chances of mortality.
- Correlation is not cause.
Alright, that stuff all makes sense – great critical commentary. Hooray for our side!
Wait a minute….. Something about the results of this study still gnaws at me. The idea that these findings are “wrong” just doesn’t sit right. Somehow, I just know that if you regularly eat lots and lots of “slim-jims”, hot dogs, steaks, ground beef, bologna and pork from the grocery store – you’ll be far more likely to get heart disease or cancer, than if you didn’t eat those foods. I’ve been to places like Ruth’s Chris Steak house and the processed meats section of the grocery store. I see the obvious, anecdotal test subjects regularly consuming these foods. I think we all do!
I have used our Paleolithic era diet as my dietary compass with smashing success for over 20 years. I eat as much red meat as I want – and I eat a lot of it. My blood work and that of all the Paleo-diet people I know comes back scoring in the highest percentiles indicating good health. So how can the diet and health of true Paleo-diet practitioners and the findings of this Harvard study be so contradictory? I submit to you that they are not. In fact, they absolutely support each other.
A vital tenet of successfully following a Paleolithic diet is ensuring that the animal foods consumed are PASTURED, NATURALLY RAISED, OR OTHERWISE AS CLOSE TO WILD AS POSSIBLE.
The difference between the meats used in this study and the meats true Paleo practitioners consume is like NIGHT VS. DAY.
Surprisingly, this fact was but a mere footnote mentioned at the end (if at all) in the many dissenting commentaries I have read that criticized this Harvard study.
I contacted The Harvard School of Public Health directly just to make sure I wasn’t missing anything here. I wanted to be sure that there was a very high likelihood the subjects in this study were eating the modern, industrially raised red meats most commonly consumed in our society. My email was returned by one of the Doctors who conducted the study.
“We did not have the information on whether the red meats were from grain-fed or grass-fed animals, and I am not aware of any other cohort studies that have this kind of data. But since the cohort was run from 1980s towards now, I assume that most of the red meats in the markets were grain-fed meats.”
In the comments part of this study, there in an attempt to address “why?” they discovered a correlation between eating modern red meat and increased mortality. Specifically, the study identifies the likely causal elements in red meat, high consumption of which are strongly associated with disease; including:
- Saturated fat
- Cholesterol levels
- Sodium
- Nitrates
This helped to confirm the high likelihood that the “unprocessed” meats especially from this study were not from “pastured, naturally raised” cows, pigs, or lambs. Specifically, addressing this list of suspected causal agents, for modern vs. pastured red meat, it reads almost like two arrows pointing in opposite directions. With respect to these factors, one type of meat (mass consumed, industrially-farmed) points to ill-health and disease, with the other (pastured, naturally raised meat) directing the other way, toward good health.
This is what actually unifies the findings of this study with the truth. You see, this study might be observational, but the health ramifications of eating our modern, confined-animal feeding operation foods, vs. those which are truly naturally raised are indeed profound. Thanks to the great scientific minds at the forefront of evolutionary science and anthropology these differences are well understood. The evidence continues to stack up. Here are a few of the highlights:
Technological developments of the industrial revolution allowed for the practice of feeding grains (primarily corn) to cattle in feedlots. In the USA, prior to 1850 virtually all cattle were free range or pasture fed and were typically slaughtered at 4-5 years. Modern feedlots hold over 100,000 cattle that are characteristically obese (>30% body fat) and a 545 kg steer can be brought to slaughter in 14 months. “Marbled” meat results from excessive triacylglycerol accumulation in muscle interfascicular adipocytes. Animals in the wild, pasture fed or free range rarely exhibit this trait. 99% of all beef consumed in the USA is now produced from grain fed, feed lot cattle. Such meat has a much higher proportion of (omega) N-6 fatty acids to (omega) N-3 and a much higher SFA (saturated fatty acid) content.
Research strongly suggests that absolute amount of dietary fat is less important than type of fat. Most SFA’s (saturated fatty acids) and trans- fatty acids are detrimental when consumed in excessive quantities. Further, the balance between (omega)n-3 and (omega) n-6 PUFA’s (poly unsaturated fatty acids) is integral in preventing chronic disease and promoting health. High intakes of SFA’s and trans-fatty acids increase the risk of CVD by elevating blood concentrations of total and LDL (low-density lipoproteins) (cholesterol). Higher intakes of (omega)n-3 PUFA’s (poly unsaturated fatty acids) may reduce CVD (cardiovascular disease) risk via reducing ventricular arrhythmias, blood clotting, serum triacylglycerol concentrations, growth of atherosclerotic plaques and blood pressure. They are also highly therapeutic in preventing or minimizing many inflammatory and autoimmune diseases.
The 6 major sources of SFA’s (saturated fatty acids) in the United States are:
1 Fatty meats
2 Baked goods
3 Cheese
4 Milk
5 Margarine
6 Butter
This trend was exacerbated as meat from grain fed cattle and livestock became the norm in the US diet. The current ratio in the USA of (omega)n-6 to (omega)n-3 PUFA’s (poly unsaturated fatty acids) has risen to 10:1 whereas the ratio in hunter-gatherer diets predominant in wild animal foods was 2:1 or 3:1.
(Origins and Evolution of the Western Diet: Health Implications for the 21st Century-Loren Cordain, Boyd Eaton)
The ostensible, large body of evidence regarding the positive health effects of eating naturally raised animals as part of a healthy diet is beyond compelling. Granted, there is a difference between typical pastured cows and the lean wild game meats that our ancestors consumed (and that many Paleo-diet people increasingly consume). No doubt, over 2000 years of animal husbandry has made our most commonly consumed meats less lean than they would have been, had they remained wild. Nonetheless, the differences are still vast when we compare these same animals, raised in a truly organic, natural way vs. their highly industrial counterparts. Pease consider this classic use of hypothetical “twins” in contemplating the lives of two newborn cows:
Twin #1
From birth, this cow will get nursed by its mother. It will then naturally begin to eat grass from the pasture wherein it roams. It will drink only clean water. Finally, it will live socially within a herd of other cows, roaming around in an expansive, natural pasture as these animals would in the wild.
Twin #2
This cow will be taken from its mother prematurely. It will not be allowed to move around. It will be raised indoors in a confined space barely larger than the animal itself. It will be force fed low grade corn, and other dead animals rendered into its feed as cheap protein. It will also be fed antibiotics to keep it alive since its unnatural diet will cause severe ill-health. This cow will also be administered growth hormone and or/steroids to make it as large as possible and speed up its growth before it is inhumanely slaughtered.
Which cow would you prefer to consume, especially knowing their parents were raised the same way? Which one do you think would be healthier one to eat? We already know the answer to this question. Now, the vast majority of the “unprocessed” cuts of meat for the Harvard study – that is, “New York and T-bone” steaks, and the really crappy hot dogs, sausages, deli meats, etc – would have all been from cows like “Twin #2”. Thus, this Harvard study only reinforces what our great minds in the world of evolutionary science have already discovered and dispensed to the rest of us. Yup, red meats from mass produced, industrially raised, grain fed (among other horribly unnatural things) animals, whether processed or unprocessed…..
ARE FREAKING BAD FOR YOU AND ARE LIKELY TO INCREASE YOUR CHANCES OF DYING
THANK YOU HARVARD!
This study just tells most Paleo-diet folks what they already knew. Modern meat, processed or unprocessed can be dangerous to your health, especially relative to its naturally raised/pastured counterpart. The processed or un-processed makes little difference to us. Hell, to us IT’S ALL PROCESSED because the poor animals are not allowed to live out their lives in their natural habitats consuming ONLY WHAT NATURE AND EVOLUTION INTENDED THEM TO CONSUME. Regardless as to whether the animal ends up in a hot dog, ground beef, or a rib-eye steak – modern industrially raised meats are inherently unhealthy.
Regardless of any congruencies of this study to the truths being exposed by evolutionary science, what is tragic about this study is the confusion it creates regarding red meat consumption. It you take the time to discover the truth, the vast nutritional difference between foods from naturally raised vs. industrially raised animals will become quite apparent. It’s important for people to know this before being confronted with the results of such studies.
For the public who may not be aware of the differences outlined above, the confusing dietary “snakes and ladders” game just continues. That is partially because strong advocates against meat consumption will use studies like this to push their respective agendas. This will be supported by the idea (incorrect or not) that red meat is really bad for you and can actually kill you. Yet, this simply isn’t true.
There is an obvious and natural corollary from this study. The useful conclusion to apply is this:
If you are going to eat food from any animal, to optimize your health and protect yourself from disease:
make sure it was naturally raised!