Are you low carb diets healthy? The “Keto Diet” or ketogenic diet is a current popular trend for weight loss. Is embarking on this radical diet worth the effort? Answering this question will depend on what works best for you. If you’re hesitant about the restrictions with this diet, you’re not alone. Not only is it a tough diet to follow, it’s unhealthy long-term and not necessary for weight loss.
Like many diets, the Keto diet prescribes a certain ratio of carbohydrates, protein, and fat or macronutrients. However, it differs from a low carb diet due to a higher ratio of fat to protein. The traditional ketogenic diet, used to lessen the frequency of epileptic seizures, is a ratio of 4 grams of fat for every 1 gram of protein plus carbohydrate. This translates to around 90% of your calories from fat, and 10% of your calories from protein and carbohydrate combined. The ratios are easy to see on an app that calculates macronutrients in percentages of total calories; MyFitnessPal is one example that shows macronutrients by percent calories. The ketogenic diet also requires low carb, usually around at most 20 grams of carbohydrate per day. Again, it’s the high amount of fat that sets this diet apart from traditional low carb/high-protein diets. Do you think you could eat only 20 grams of carbs per day? One clementine, or a “cutie”, has about 10 grams of carbohydrate, or 50% of your daily allowance. Yikes!
The Keto diet is effective for weight loss, but so are many other diets. The evidence does not exclusively support low carb as the only method for weight loss. Yes, some research has shown increased weight loss with lower carbohydrate diets. A 2006 meta-analysis of weight loss in an “Atkins” diet (<10% kcals from carbohydrate), found a difference of 7.26 lbs after 6 months with “Atkins” versus low-fat or calorie restriction.1 A long-term study comparing low carb diets, Mediterranean, and low-fat, found greater weight loss in the low carb diet by about 5 lbs after 2 years.2 But are you willing to restrict your diet for a difference of 5 lbs over 2 years? Other studies have shown that after 1 year, a low carbohydrate/high-protein diet did not offer better weight loss results compared to a high carbohydrate/low-fat diet. 3,4,5,6,7,8,9 Strict diets are hard to follow and the only effective diet is one that you can follow long-term.
Not only is a well-balanced diet high in variety easier to stick to, it is also more nutritious. Nutritional deficiencies with a long-term low carb diet are an important consideration. In general, the diet restricts fruit, some vegetables, and whole grains, reducing overall fiber intake; vitamins A, E, and B6, thiamin, and folate; calcium; potassium; magnesium; and iron. Low carb diets as practiced in the general population are typically higher in saturated fat and cholesterol. A study measuring the healthy eating index of popular diets showed that high-carbohydrate diets resulted in the highest dietary adequacy score of 82.9, while the low carb score was 44.6 out of 100. There is strong evidence for the protective effects against cancer for whole grain, fruit, and vegetable consumption; these cancers include colorectal, breast, pancreatic, lung, stomach, oesophageal, and bladder cancers 10. A cohort investigation in an adult Greek population found a significant increase in mortality with a low-carbohydrate/high-protein diet in a group without coronary artery disease, diabetes, and cancer at baseline. When controlled for energy intake, low carb/high protein was associated with an 8% increase in mortality 11.
Still biting your nails over how to lose weight? Making a nutrition plan that will work for you is a key step and results in long-term success. Registered dietitians (RD) are the only credentialed medical professional for nutrition information and counseling. Not only can RDs help you lose weight, they can tailor your care to other chronic concerns ranging from irritable bowel syndrome, heart disease, and diabetes. No time to make another doctors appointment? Take advantage of telenutrition to get personalized counseling in the comfort of your own home. Check out available appointments today.
- Clifton P. Low-carbohydrate diets for weight loss: the pros and cons. J Hum Nutr Die. 2011;24:523-524.
- Shai I, Schwarzfuchs D, Henkin Y, et. al. Weight Loss with a Low-Carbohydrate, Mediterranean, or Low-Fat Diet. N Engl J Med. 2008;(359):229-241.
- Foster J, Wyatt H, Hill J. A randomized trial of a low-carbohydrate diet for obesity. N Engl J Med. (348):2082-2090.
- Due A, Toubro S, Skov A, Astrup A. Effect of normal-fat diets, either medium or high in protein, on body weight in overweight subjects: a randomised 1-year trial. Int J Obes Relat Metab Disord. 2004;(28):1283-1290.
- Das S, Gilhooly C, Golden J, et. al. Long-term effects of 2 energy-restricted diets differing in glycemic load on dietary adherence, body composition, and metabolism in CALERIE: a 1-y randomized controlled trial. Am J Clin Nutr. 2007;(85):1023-1030.
- Stern L, Iqbal N, Seshadri P, et. al. The effects of low-carbohydrate versus conventional weight loss diets in severely obese adults: one-year follow-up of a randomized trial. Ann Intern Med. 2004;(140):778-785.
- Dansinger M, Gleason J, Griffith J, Selker J, Schaefer E. Comparison of the Atkins, Ornish, Weight Watchers, and Zone diets for weight loss and heart disease risk reduction: a randomized trial. JAMA. 2005;(293):43-53.
- Luscombe-Marsh N, Noakes M, Wittert G, Keough J, Foster P, Clifton P. Carbohydrate restricted diets high in either monounsaturated fat or protein are equally effective in promoting fat loss and improving blood lipids. Am J Clin Nutr. 2005;(81):762-772.
- Keogh J, Luscombe-Marsh N, Noakes M, Wittert G, Clifton P. Long-term weight maintenance and cardiovascular risk factors are not different following weight loss on carbohydrate-restricted diets high in either monounsaturated fat or protein in obese hyperinsulinemic men and women. Br J Nutr. 2007;(97):405-410.
- Crowe TC. Safety of low-carbohydrate diets. Obesity Reviews. 2005;6(3):235-245. doi:10.1111/j.1467-789X.2005.00196.x.
- Trichopoulou, A., Psaltopoulou, T., Orfanos, P., Hsieh, C.-C, Trichopoulos, D. Low-carbohydrate–high-protein diet and long-term survival in a general population cohort. European Journal of Clinical Nutrition. 2007;61(5):575-581. doi:10.1038/sj.ejcn.1602557.