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Ketogenic Diets For Weight Loss: Documented adverse side effects and other concerns
James Meschino DC, MS, ROHP
I get many questions, and am often challenged by people, in regards to my reluctance to acknowledge the ketogenic diet as a safe weight loss program, and one that is superior to weight loss programs that allow more generous amounts of carbohydrates. My position is based on the peer-reviewed scientific literature that has emerged over the past twenty years, and has been summarized succinctly in the review article by Margo A. Denke MD, published in the American Journal of Cardiology in 2001. In short, ketogenic diets used for weight loss do not result in more efficient or a faster reduction in body fat than do restricted calorie diets that provide a greater amount of carbohydrate calories, and which do not put the patient into a state of ketosis. Moreover, ketogenic diets used for weight loss have been shown to reduce lean mass (muscle mass) by approximately 25%, which ultimately slows metabolism. This is likely one of the reasons that over 90% individuals who lose weight using this method (as well as other drastic dietary practices) have been shown to regain all the weight they lost on the diet within a 2-year period.
Documented Adverse Effects of Weight Loss Ketogenic Diets
In the medical world ketogenic diets have been used successfully for many years to manage seizure disorders in children with uncontrollable seizure disorders. This has allowed researchers to track and monitor long-term side effects of individuals who have faithfully employed the ketogenic diet as a health necessity. It is well documented that these patients are at much greater risk for dehydration, constipation, impaired immunity (via impaired neutrophil function), kidney stones and osteoporosis.
Published studies, involving overweight adult patients adopting the Dr Atkins and/or Dr Stillman ketogenic diet programs, showed that these patients experienced a significant rise in their LDL-cholesterol level within weeks of starting the diet. High LDL-cholesterol is a cardinal risk factor for cardiovascular disease – the leading killer in our society. Ketogenic diets also promote a rise in blood uric acid levels, which is also a risk factor for cardiovascular disease, as well as for the development gouty arthritis.
The high protein nature of the ketogenic diet also results in increased acidity in the blood and urine. To buffer the blood acidity the body leaches calcium out of bones (via parathyroid hormone secretion), which encourages the development of osteoporosis. As noted above, osteoporosis is a well documented side effect of long-term use of a ketogenic diet. Complications from osteoporotic fractures result in more deaths each year than the combined mortality rate for breast and ovarian cancer (Canadian Osteoporosis Society).
The increase in urine acidity encourages the formation of kidney stones and patients on ketogenic diets have been shown to be at greater risk for kidney stone formation and attacks. Studies also confirm that the high protein content of the ketogenic diet encourages the progression of any existing chronic renal (kidney) insufficiency, failure or compromised kidney function. There are also concerns that the high levels of circulating fatty acids, resulting from the ketogenic diet, may contribute to pro-arrhythmia effects on the heart, increasing risk for sudden death.
Effective Weight Loss: Ketogenic Diet versus Calorie Restriction With Greater Carbohydrate Intake
Some argue that ketogenic diets produce faster weight loss than other forms calorie-restricted diets. This is because ketogenic diets quickly deplete muscle and liver glycogen (carbohydrate) stores. Carbohydrates are heavy fuels, which hold a greater amount of water within their structure. Depletion of carbohydrate stores results in rapid weight loss, along with concurrent dehydration from rapid water loss (via urine). However, depleting carbohydrate stores is not desirable. It makes it virtually impossible to exercise even moderately. Without moderate exercise muscle tissue breaks down during any weight loss program. Loss of muscle mass (made of protein) slows the body’s resting metabolic rate. If metabolism is allowed to slow down from muscle breakdown studies show it becomes very likely the patient will gain the weight back that they lost, and even exceed their initial pre-diet weight (weight loss rollercoaster effect). Ketogenic diets do not result in greater loss of body fat than other calorie-restricted diets that allow more carbohydrate foods.
To be healthy you need a minimum amount of physical activity per week (burning 2000 calories minimum), according to longevity studies. This can be accomplished by a simple walking program. The carbohydrate depletion (glycogen) imposed by the ketogenic diet robs muscles of the carbohydrate energy needed for individuals to be engaged in meaningful amounts of physical activity. As well, many plant-based carbohydrate foods contain vital phytonutrients that have been shown to reduce risk of cancer and heart disease. Many of these foods also buffer the blood, reducing acidity and thus, have been shown to help maintain bone density. Many carbohydrate foods also exert positive effects on bowel function, improving regularity, eliminating carcinogens and reducing risk of diverticular disease.
There is no doubt that restricting refined, sugary, carbohydrate foods is important in any weight management program, as well as being important to the overall reduction in risk of diabetes, cancer, heart disease, dementia, impaired immunity and other problems. Regarding starchy carbohydrate foods (bread, pasta, rice, potatoes), the more active an individual is, the greater becomes the window for starchy carbohydrate intake. Individuals performing regular endurance activity require some starchy carbohydrates in order to replenish their liver and muscle glycogen stores. This allows them to find the energy to engage in moderate endurance, fat-burning activity, day after day. By this process the individual loses body fat, preserves muscle mass, does not slow their metabolism, develops new behaviours to ensure their long-term success, does not become dehydrated and reduces their risk of cardiovascular disease, osteoporosis and cancer.
I have provided the exact details of how to implement a prudent weight management program,which does not put the patient into a state of ketosis, in my book“The Meschino Optimal Living Program – 7 steps to a healthy, fit, age-resistant body”. Having used this program with hundreds of patients I would strongly recommend that a patient use this program as safe, easy, effective method to lose body fat and enhance their health, instead of ketogenic diet, for all the reasons outlined in this review
No difference in weight loss (no advantage), compared to calorie restriction (prudent diet)
Dieting – 95% rate of failure over 2 years
Increased water loss and glycogen depletion – weakness –cant excercise
Children on Ketogenic diet Seizures:
Dehydration, constipation, kidney stones, impaired neutrophil function, optic neuropathy, osteoporosis
Complications In Adults Documented
Atkins – significant rise in LDL cholesterol
Stillman significant rise in LDL cholesterol
High fatty acids known to have pro-arrhythmia effects
Lack of phytonutrients and vits and mins
Elevated uric acid levels (gout and CVD stickiness etc)
Lower urinary pH increases kidney stone formation
Osteoporosis from acid load – buffering system –calcium
Progression of chronic renal insufficiency
Reference: Journal of Cardiology