In recent years, the ketogenic diet has been attracting a lot of attention for the management of numerous health conditions, as well as for weight loss. Some controversy still exists about its safety and efficacy, largely stemming from a lack of longitudinal and mechanistic studies, inconsistencies in diet composition in different cohorts, and disagreement in conclusions between research conducted on animal vs. human populations.

Elena Paravantes, RDN is a Registered Dietitian Nutritionist, Writer and consultant specializing in the Greek Mediterranean Diet and Cuisine. She has been active as a clinician, consultant and lecturer for 20 years, both in the U.S. and Greece. An expert on the Greek Mediterranean Diet, her interviews and articles have been published in many publications including CNN, U.S. News and World Report, Prevention, NPR, and Shape. Elena has collaborated with a number of organizations including Loyola University, Yale University, University of Missouri, Louisiana State University, and the American College of Greece.
When compared to the calorie-restrict diet, the subjects who underwent the ketogenic diet experienced a reduction three times greater in hemoglobin A1C (1.5% vs. 0.5%). [9] In addition to observing greater improvements in diabetes-related markers, researchers observed a greater reduction in medication usage in subjects that underwent the ketogenic diet treatment. Thus, due to their overall findings, the researchers stated that “Lifestyle modification using low carbohydrate interventions is effective for improving and reversing type 2 diabetes.” [9]
When your body burns its stores of fat, it can be hard on your kidneys. And starting a ketogenic diet -- or going back to a normal diet afterward -- can be tricky if you’re obese because of other health issues you’re likely to have, like diabetes, a heart condition, or high blood pressure. If you have any of these conditions, make diet changes slowly and only with the guidance of your doctor.

Although some studies have indicated that a ketogenic diet is associated with dyslipidemia (cholesterol and triglyceride perturbations), many of these results were obtained from studies on rodents and did not always agree with what the data show in human studies. A recent review summarized the controversy, highlighting the discrepancies in the literature. In part, the discordance is likely due to the exact composition of the diet, specific study design, as well as the metabolic differences between rodents and humans.

Meanwhile, more than 70 trials have examined the health effects of a low-carb diet. They attest to the benefits64 associated with ketosis and low-carb diets, including a reduction in body weight and body mass index, improved cardiovascular risk factors including blood pressure, and the reversal of Type 2 diabetes. It is virtually impossible to imagine that a diet with so many health improvements in the ‘near term’ (2 years) could ultimately shorten life—and the study authors offer no possible mechanism to explain how this might happen.


Con: Results can vary depending on how much fluid you drink. By drinking more water, you dilute the concentration of ketones in the urine and thus a lower level of ketones will be detected on the strips. The strips don’t show a precise ketone level. Finally, and most importantly, as you become increasingly keto-adapted and your body reabsorbs ketones from the urine, urine strips may become unreliable, even if you’re in ketosis.
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