What to eat? Low fat foods, high fat foods…..?Posted: July 12, 2014
Meat for sale (tongue and liver) at a traditional market (photo by Erik Peper).
Should I eat vegetables or meats? Should it be steaks or organ meats such as liver, heart, sweet breads? What foods contributes most to heart disease or cancer? Should I change my diet or take medications to lower my cholesterol?
Despite the many years of research the data is not clear. Many public health dietary guidelines and recommendations were based upon flawed research, researchers’ bias and promoted by agribusiness. Starting in the 1950s there has been a significant change in the dietary habits from eating animal fats to plant based oils and fats. It is so much cheaper to produce plant based polyunsaturated salad or cooking oils (e.g. Wesson and Mazola) and hydrogenated hardened oils (e.g. margarine and Crisco) than animal fats (e.g., butter, beef tallow, and lard). Despite the many claims that lowering animal fat intake would reduce heart disease and possibly cancer, the claims are not supported by research data. It is true that consuming liquid plant based oils lowers the cholesterol, but with the possible exception of olive oil, polyunsaturated oils are associated with an increased cancer and death rates in large population studies (Multiple Risk Factor Intervention Trial Research Group,1982; Shaten, 1997).
We assume that lowering cholesterol is healthy; however, it is usually a surrogate marker representing a hypothesized improvement in health. A short term apparent reduction in cholesterol levels or other illness markers may mask the long term harm. Only long term outcome studies which measure the total death rate– not just from one disease being studied but from all causes of death–provides the objective results. When looking at the results over a longer time period, there appears to be no correlation between fat intake and heart disease. In fact lowering fat intake seems to be associated with poorer long term health as described in the outstanding book, The Big Fat Surprise–Why Butter, Meat & Cheese Belong in a Healthy Diet, by the science writer, Nina Teichol. Her superb investigative reporting describes in detail the flawed and biased research that underpinned the United States Department of Agriculture (USDA) and the American Heart Association (AHA) recommendations to reduce animal fats and use more plant based oils.
What should I eat now?
Diet recommendations used to be simple: Reduce animal fat intake and eat more plants. Now, there are no simple recommendations because they may depend upon your genetics (e.g., digestion of milk depends whether you are lactose tolerant or intolerant), your epigenetics (e.g., maternal malnutrition during your embryological development is a major risk for developing heart disease in later life), your physical and social activities (e.g., exercise reduces the risk for many diseases), and environment. The recent popularity of the hunter and gatherer diet, often known as the paleo diet, is challenging–it may depends on your ancestors. What hunter and gatherers ate depended upon geography and availability of food sources. The Inuit’s diet in the Arctic consisted of 90% meat/fish diet while the !Kung Bushman’ diet from the Kalahari desert in Africa consisted of less than a 15% meat/fish diet as shown in Figure 1.
Figure 1. The food content of hunter gatherers varied highly depending on geography. From: Jabr, F. (2013). How to Really Eat Like a Hunter-Gatherer: Why the Paleo Diet Is Half-Baked. Scientific American, June 3.
Use common sense to make food choices.
- Eat only those foods which in the course of evolution have been identified as foods. This means eating a variety of plants based foods (fruits, tubers, leaves, stems, nuts, etc.) and more organ meats. Ask yourself what foods did your forefathers/mothers ate that supported survival and reproductive success. Carnivores usually ate the internal organs first and often would leave the muscles for scavengers.
- Eat like your great, great grandparents. They were not yet brainwashed by the profit incentives of agribusiness and pharmaceutical industry. For more information, read the outstanding books by Michael Pollan, The Omnivore’s Dilemma: A Natural History of Four Meals and In Defense of Food: An Eater’s Manifesto.
- If possible eat only organically grown/raised foods. Non organic foods usually contain low levels of pesticides, insecticides, antibiotics and hormones which increases the risk of cancer (Reuben, 2010). They may also also contain fewer nutrients such as essential minerals, vitamins, and antioxidants (Barański et al, 2014). The beneficial effects of organic foods have been challenging to demonstrate because it may take many years to show a difference. Preliminary data strongly suggests that organic foods as compared to non organic foods increases longevity, improves fertility and enhances survival during starvation (Chhabra, Kolli, & Bauer, 2013). For more information, see my blog, Live longer, enhance fertility and increase stress resistance: Eat Organic foods.
- Adapt the precautionary principle and assume that any new and artificially produced additives or chemically processed foods–most of the foods in boxes and cans in the central section of the supermarket–contain novel materials which have not been part of our historical dietary experience. These foods may be harmful over the long term and our bodies not yet know how to appropriately digest such foods such as trans fats (Kummerow, 2009).
- Be doubtful of dietary recommendations especially if you know of counter examples and exceptions. For example, the low fat diet recommendations could not explain the French or Swiss paradox (high butter and cheese intake and low heart disease rates). If examples exist, the popular dogma is incomplete or possibly wrong. Be skeptical about any health food claims. Ask who has funded the research, who decides whether a food can have a label that states “it is heart health” and can prevent a disease, and who would benefit if more of this food is sold.
My final comments on nutrition (source unknown).
- The Japanese eat very little fat and suffer fewer heart attacks than us.
- The Mexicans eat a lot of fat and suffer fewer heart attacks than us.
- The French eat lots of butter and drink alcohol and suffer fewer heart attacks than us.
- The Chinese drink very little red wine and suffer fewer heart attacks than us.
- The Italians drink a lot of red wine and suffer fewer heart attacks than us.
- The Germans drink a lot of beer and eat lots of sausages and fats and suffer fewer heart attacks than us.
Eat and drink what you like especially if you enjoy it with company…speaking English is apparently what kills you!
Jabr, F. (2013). How to Really Eat Like a Hunter-Gatherer: Why the Paleo Diet Is Half-Baked. Scientific American, June 3.http://www.scientificamerican.com/article/why-paleo-diet-half-baked-how-hunter-gatherer-really-eat/
Kummerow, F. A. (2009). The negative effects of hydrogenated trans fats and what to do about them. Atherosclerosis, 205(2), 458-465.http://www.atherosclerosis-journal.com/article/S0021-9150%2809%2900208-1/abstract
Multiple Risk Factor Intervention Trial Research Group. (1982). Multiple risk factor intervention trial. JAMA: The Journal of the American Medical Association, 248(12), 1465-1477. http://jama.jamanetwork.com/article.aspx?articleid=377969
Pollan, M. (2006). The Omnivore’s Dilemma: A Natural History of Four Meals. New York: Penguin Press. ISBN: 1594200823
Pollan, M. (2009). In Defense of Food: An Eater’s Manifesto. New York: Penguin Press. ISBN: 978-0143114963
Reuben, S. H. (2010). Reducing environmental cancer risk: what we can do now. DIANE Publishing. http://deainfo.nci.nih.gov/advisory/pcp/annualReports/pcp08-09rpt/PCP_Report_08-09_508.pdf
Shaten, B. J., Kuller, L. H., Kjelsberg, M. O., Stamler, J., Ockene, J. K., Cutler, J. A., & Cohen, J. D. (1997). Lung cancer mortality after 16 years in MRFIT participants in intervention and usual-care groups. Annals of epidemiology, 7(2), 125-136. http://www.annalsofepidemiology.org/article/S1047-2797%2896%2900123-8/abstract
Teicholz, N. (2014). The big fat surprise-Why butter, meat & cheese belong in a healthy diet. New York: Simon & Schuster. ISBM 978-1-4516-2442-7 http://www.thebigfatsurprise.com/