|Post-Workout at CrossFit Seven in Fort Worth, TX.|
The answer to the post headline is: low-carb high protein diets are probably not good for Masters. Or for younger athletes either. The news is that a major study found increased cardiovascular disease in women who consumed a lot of protein relative to carbohydrate. The more carbohydrate intake was restricted the greater the risk of having a heart attack, stroke, embolism or vascular disease. This supports findings from several other human studies (Fung et al. 2010, Lagiou et al. 2007, Trichopoulou et al. 2007). Several of our posts have shown benefits from protein intake for masters athletes. The messages to take away here are that excessively restrictive diets are not good and that carbohydrates are not bad. You can harm yourself in being carbophobic. Get enough protein to protect muscle strength but don’t go off the deep end. If you are following a Paleolithic Diet (The Paleo Diet, which is promoted by a lot of Cross Fit Boxes) you should still be able to eat a very reasonable amount of carbohydrates. This is a Cross Fit Cross Fit matter. A lot of CrossFitters are very detailed and committed to their training, diet and health in general. Its good to be committed. Just not good to be committed to, or go overboard on, something that’s not in your best interest.
More study would be needed to see how protein source plays into cardiovascular disease. High intake of vegetable protein is associated with smaller waist circumference and lower BMI. People who eat a lot of animal protein tend to have a thicker waist circumference and higher BMI.
There are a lot of questions to raise with this including the possibility that people who eat less animal protein consume less animal fat. Animal fat can be a rich source of bioactive, lipophilic contaminants. It has recently been reported that exposure to “Persistent Organic Pollutants” which accumulate in fat cause insulin resistance (Ruzzin et al. 2010). The problem may not be high protein intake. It might be exposure to contaminated animal fat. Or it might be low carbohydrate intake. We don’t know yet.
BMI, blood lipid profiles and incidence of cardiovascular disease in matched cohorts of grass-fed/organic animal protein eaters vs. regular grocery store consumers have not been studied. It will be interesting to see what comes up over the next few years. In the meantime, remember that 22-year-olds who have been to a workshop are not necessarily the best sources of dietary information. Go Masters!
Ruzzin J, Petersen R, Meugnier E, Madsen L, Lock EJ, Lillefosse H, Ma T, Pesenti S, Sonne SB, Marstrand TT, Malde MK, Du ZY, Chavey C, Fajas L, Lundebye AK, Brand CL, Vidal H, Kristiansen K, & Frøyland L (2010). Persistent organic pollutant exposure leads to insulin resistance syndrome. Environmental health perspectives, 118 (4), 465-71 PMID: 20064776
Lin, Y., Bolca, S., Vandevijvere, S., De Vriese, S., Mouratidou, T., De Neve, M., Polet, A., Van Oyen, H., Van Camp, J., De Backer, G., De Henauw, S., & Huybrechts, I. (2010). Plant and animal protein intake and its association with overweight and obesity among the Belgian population British Journal of Nutrition, 1-11 DOI: 10.1017/S0007114510004642
Fung TT, van Dam RM, Hankinson SE, Stampfer M, Willett WC, & Hu FB (2010). Low-carbohydrate diets and all-cause and cause-specific mortality: two cohort studies. Annals of internal medicine, 153 (5), 289-98 PMID: 20820038
Trichopoulou A, Psaltopoulou T, Orfanos P, Hsieh CC, & Trichopoulos D (2007). Low-carbohydrate-high-protein diet and long-term survival in a general population cohort. European journal of clinical nutrition, 61 (5), 575-81 PMID: 17136037
Lagiou P, Sandin S, Weiderpass E, Lagiou A, Mucci L, Trichopoulos D, & Adami HO (2007). Low carbohydrate-high protein diet and mortality in a cohort of Swedish women. Journal of internal medicine, 261 (4), 366-74 PMID: 17391111