Animal protein can kill you? Really?
Study published in the journal of Cell Metabolism says diet high in animal protein may kill you prematurely if you are between the ages 50 to 65. If you are over 65 then animal protein may protect you.
One of the headlines online read: Diet High in Meat, Cheese Can Be as Bad as Smoking
• This was an observational epidemiological study where researchers look at the relationship with one or more occurrences (consumption of animal proteins) and its relationship to (in this case) disease and death.
• 6,381 US men and women aged 50 and above were observed for 18 years.
• The participants were categorized into three groups based upon their protein consumption (low, med, high). High= 20% of calories from protein; Moderate = 10-19% of calories from protein; Low=10%.
• Average calorie intake was reported as 1,823 per day – 51% from carbohydrate; 33% from fat and 16% from protein. Most of this protein intake was reported as protein from animal sources.
• Results showed that the higher the protein intake from animal sources the higher the all-cause mortality ONLY in middle-aged people (50 to 65) by 74%
• Studied subjects who were 65 and over proved to do poorly on a low protein diet and benefit from a higher protein diet.
• In mice “A 45% smaller mean tumor size was also observed in the low protein group compared to the high protein group at the end of the experiment at day 53”. (By the way, rodents are herbivores so they naturally do worse with protein. I’m just saying.)
• Researchers conclusion: Plant-based nutrients maximize health benefits in all age groups.
– Levine et al. 2014
Here’s the breakdown of the categorization of protein intake linked to mortality between studied subjects:
Age 50-65 – All-cause Mortality
• Low: 18.07%
• Mod: 20.28%
• High: 26.15%
Age 50-65 – Cancer Mortality
• Low: 2.58%
• Mod: 7.89%
• High 9.89%
Age 66+ – All-cause Mortality
• Low: 70.97%
• Mod: 63.73%
• High: 64.04%
Age 66+ – Cancer Mortality
• Low: 18.03%
• Mod: 12.94%
• High 7.96%
Here’s a head scratcher from this research: One of the main study author’s who obtained funding from the Nation Institutes of Health (NIH) is Victor D. Longo, PHD. Dr. Longo is co-founder of L-Nutra, a company that develops plant-based foods where he has equity interest. The conflict of interest potentiality here raises “red flags”.
My Take On This
Kudos to the researchers for the publication of this study despite the fact that it’s still inconclusive by nature of it being an observational epidemiological study. These types of studies are hard to manage and are very expensive. The “name of the game” in research is to obtain as many participants to study as possible and run the study for as long as possible. To make a study conclusive the design needs to be randomized where one group is exposed to a chemical of interest (known as the experimental group) and the other group provided with a placebo (known as the control group). This study “batted 2 for 3” – it studied a large number of people and ran the study for 18 years. However, it was not randomized.
If you lump all the “good” observational studies together you may get some nice clues that may improve health, prevent disease and increase longevity.
Clues are NOT conclusions however.
To make causal conclusions from observational studies is inappropriate and misguiding.
Also, I do not think Dr. Longo should have been involved in this study due to his association with a plant food company and potential conflict of interest. However , he has openly responded to most concerns and questions posed by other scientist regarding the study. He also seems to be well aware of the shortcomings of his research based from his responses.
It is not Dr. Longo’s fault that the media is thirsty for headlines and sound bytes and make outlandish conclusions that are not representative of the research observed as they did when reporting the results of this study.
So, will consuming animal protein kill you?
The study makes an association that it may but there are too many other factors overlooked and not controlled for.
If you look above at the study details and breakdown, this study does not necessarily show that there’s much of an increase in cancer from animal products consumption but ONLY a significant increase in ALL CAUSE mortality with high increase of animal products.
Not controlling for other variables such level of physical activity, other dietary habits, source of animal products eaten (poultry, fish, red meat) makes any association even more difficult. Meat eaters typically eat a Standard American Diet (SAD) and live unhealthy lifestyles; they consume less fruits/veggies, eat loads of refined carbohydrates, are sedentary, smoke and drink loads of coffee and alcohol.
Lastly, the quality and type of meats consumed was not looked at by Levine et al. Organic, grass-fed meats, as opposed to corn and grain-fed meats are substantially different nutritionally. Several studies suggest’ that grass-based animal products have higher levels of Vitamin A and E, as well as cancer fighting antioxidants such as glutathione and superoxide dismutase, lower in fat and higher Conjugated Linoleic Acid (CLA) and Omega-3 Fatty Acids ( the good fat) compared to corn and grain-fed animals. (Daley et al. 2010)
What should you do?
• Do not believe the false notion that meats and animal products are bad for you. It is not.
• The focus should not only be on what you should NOT eat but, on what you SHOULD eat.
• I have clinically learned that animal product consumption does not agree with some people. Makes them feel lethargic and “heavy” long after consumption. Maybe meat proteins from such person is not good to eat.
• Dr. Peter D’Adamo, for example has observed that those that are blood type A do not do well with meat consumption. It turns out that people that are blood type A make less hydrochloric acid – an important component to digesting meats properly.
• There’s a difference with bad meats (conventional, grain and corn-fed type) and good meats (grass-fed type)
• When eating animal products consume the good type as much as possible. No limits, really.
• When eating the bad variety, eat them least frequently if at all. About once or twice a month is fine. So at a steak house, for example have a good medium rare with broccoli, a glass of red wine and maybe some green tea towards the end will not cause harm. OK, an espresso is fine too. Leave the bread-basket alone though.
• Preparation of meats is key. Do not overcook or grill meats as this prep technique is most cancer causing. (Zheng 2010)
• It’s not only about what you don’t want to eat and but more importantly what you should eat. Eating plenty of plant foods, vegetable and fruits.
• Limit or exclude refined carbohydrates and sugar consumption. Pretty much every health expert agrees these foods are the biggest culprit to mortality. And these are the most addictive by the way.
• Fitness is important so get moving as much and often as possible.
• And No. Meat consumption is NOT even remotely as bad as smoking.
Daley C.A., Abbott A., Doyle P.S.et a: A review of fatty acid profiles and antioxidant content in grass-fed and grain-fed beef. Nutr J 2010; 9: 10
Zheng W1, Lee SA. Well-done meat intake, heterocyclic amine exposure, and cancer risk. Nutr Cancer. 2009;61(4):437-46.
Morgan E. Levine, Jorge A. Suarez, Sebastian Brandhorst, Priya Balasubramanian, Chia-Wei Cheng, Federica Madia, Luigi Fontana, Mario G. Mirisola, Jaime Guevara-Aguirre, Junxiang Wan, Giuseppe Passarino, Brian K. Kennedy, Min Wei, Pinchas Cohen, Eileen M. Crimmins, Valter D. Longo. Low Protein Intake Is Associated with a Major Reduction in IGF-1, Cancer, and Overall Mortality in the 65 and Younger but Not Older Population. Cell Metabolism, 2014; 19 (3): 407-417
Other good blogs responding to this study:
Jason Cholewa – CLICK HERE
Zoe Harcombe – CLICK HERE