By Jeff Thiboutot
Low carbohydrate (CHO) food plans/diets have been around for a long time. For instance, William Banting, in 1864, wrote a book on low CHO eating called Letter on Corpulence (Bowden). Additionally, there have been a number of populations, such as the Eskimos (Inuit) of Alaska and Masai tribe in Africa, that have been eating a low CHO diet for thousands of years and have been exceptionally healthy. Ever since then there have been surges of popularity in this type of eating (i.e., Atkins, South Beach, etc.). The question is; is this type of eating healthy and does it help with weight loss? The simple answer is an overwhelming yes!
Eating a low-CHO diet, often considered to be 10-40% of caloric intake as carbohydrates, has been extensively researched over the past three decades. However, there has been some published research on low CHO eating as early as 1926. The 1926 article, titled “The effects of an exclusive long-continued meat diet”, was published in the Journal of the American Medical Association. The results of this long study showed no harmful effects from eating a very low CHO, med protein, and high fat diet (Lieb et al). Another early study, published in the New England Journal of Medicine in 1953, demonstrated positive effects on weight loss and no negative health effects were noted (Bowden).
Back to today. There have been dozens of studies on low CHO diets. The collective result from all these studies is the fact that this type of eating, relative to higher CHO, low protein, low fat diets, has much better effects on appetite control, fat loss, and blood markers of cardiovascular disease (CVD) risk, such as HDL, triglycerides, insulin, and blood sugar (Volek et al, 2005; Volek et al, 2004; Volek et al, 2002; Meckling et al, 2007; Foster et al, 2003; Golay et al, 1996; Accurso et al, 2008). Most recently, July 17, 2008, a paper was published in the New England Journal of Medicine. The paper was the result of a 2 year study on the effects of three different diets; low-carbohydrate, Mediterranean, and low-fat diet. The results from this study demonstrated that the low CHO diet had the best results regarding weight loss and metabolic markers of CVD risk. All the diets induced weight loss, and some improvement in CVD markers, but the low CHO diet induced the best changes (Shai et al, 2008).
To continue to state that a low CHO diet is ineffective and harmful is a red flag of ignorance on the subject (Manninen). This does not mean that everyone needs to eat this way to improve their weight and health. However, from the currently available evidence, it certainly seems that it typically is the most efficient and effective method. Also, eating a low CHO diet may not have to be followed forever. When a goal weight and other health markers are achieved some people can start to increase their CHO intake. However, others may need, for weight and health issues, to eat in a similar fashion continually. The amount of CHO that can be increased will depend on the person, but eating a diet that is up to 50% CHO is certainly possible and not unhealthy. As CHO increases, fat intakes will need to decrease proportionally and protein intake may decrease a little also.
One last point on a low CHO diet, it is not really a high protein diet, but is actually a high fat diet. The typical ranges for macronutrient ratios, based on the percentage of calories, are; 10-40% carbohydrates, 20-30% protein, and 40-60% fat. For a 1,500 calories diet this would equate to 38 – 150 grams of carbohydrates, 75 – 115 grams of protein, and 66-100 grams of fat. Typically, the intake of these macronutrients should be spread out over 3 or 4 meals a day. There are times when more or less frequent meals should be utilized but that is outside the scope of this article and will be dealt with on another occasion.
This article is meant to give a brief overview of low CHO diets regarding weight loss and overall health. For more detailed information on low CHO diets I would recommend the Nutrition and Metabolism Society (www.nmsociety.org) and any of the references used for this article. Also, there is a low carb food pyramid handout that is a good compliment to this article. It is available at L.E.A.N. U.
References:
Accurso, A. et al (2008). Dietary carbohydrate restriction in type 2 diabetes mellitus and metabolic syndrome: time for a critical appraisal. Nutrition and Metabolism. 5:9
Bowden, J. (2005). Living the low carb life. New York. Sterling.
Foster, GD. et al (2003). A randomized trial of a low carbohydrate diet for obesity. NEJM. 348: 2082-2090.
Golay, A. et al (1996). Weight loss with low or high carbohydrate diet? Int J Obes Relat Metab Disord. 20: 1067-1072.
Lieb, C. et al (1926). The effects of an exclusive long continued meat diet. JAMA. 87(1): 25-26.
Manninen, A. (2004). Metabolic effects of the very low carbohydrate diets: Misunderstood “villains” of human metabolism. J Inter Society Sports Nutr. 1(2): 7-11.
Mechling, KA. & Sherfey, R. (2007). A randomized trial of a hypocaloric high-protein diet, with or without exercise, on weight loss, fitness, and markers of the Metabolic Syndrome in overweight and obese women. Appl Physiol NutrMetab. 32(4): 743-752.
Shai, I. Et al (2008). Weight loss with a low-carbohydrate, Mediterranean, or low-fat diet. NEJM. 359(3): 229-241.
Volek, J. et al (2002). Very low carbohydrate weight loss diets revisited. Cleveland Clinic J Medicine. 69 (11): 849-862.
Volek, J. et al (2004). Comparison of energy-restricted very low-carbohydrate and low-fat diets on weight loss and body composition in overweight men and women. Nutrition and Metabolism. 1:13.
Volek, J. et al (2005). Corbohydrate restriction improves the features of Metabolic Syndrome. Metabolic Syndrome may be defined by the response to carbohydrate restriction. Nutrition and Metabolism. 2(31).
The nutritional information in this material is for educational purposes only. The information is not offered to treat, mitigate or cure disease, and should not be used as a substitute for sound medical advice. This information is designed to be used in conjunction with the services of a trained licensed healthcare practitioner.