By now you've more than likely heard of the high-fat, moderate protein [1], and low-carb ketogenic diet [2]. The keto diet is often followed by those with epilepsy and type 2 diabetes [3], and most recently it's been one of the go-to diets for weight loss [4].

If you're following the keto diet to lose weight, one of the most important rules to abide by is the macronutrient profile. According to Catherine Metzgar, PhD, RD, and a clinical team member at Virta Health [5] the macronutrient profile should be close to 70 to 80 percent fat, 15 to 20 percent protein, and five to 10 percent carbs. By following this macronutrient profile, you'll be able to reach nutritional ketosis [6] — the state where the body begins to burn ketones and fat for energy instead of glucose (carbohydrates).

"The target number of total carbs that allows one to achieve and sustain nutritional ketosis varies from one individual to another," said Stephen Phinney, MD, PhD, chief medical officer at Virta Health. According to Dr. Phinney, if you're overweight and starting the keto diet, you should aim for 30 to 50 grams of carbohydrates per day in order to achieve nutritional ketosis. In contrast, "a very active athlete might tolerate 50 to 100 grams per day," Dr. Phinney told POPSUGAR. In both cases, Dr. Phinney advises keeping protein moderate and the carbohydrates low enough to maintain keto adaption.

The best way to know if you're in ketosis [7] is by checking your blood ketone levels with blood test strips [8]. Ketone levels at or above 0.5 mM (millimolar) indicate you're in ketosis. Other options include doing a urine test or by using a breath analyser. The ketones in your blood, breath, and urine vary and can be hard to compare. If your goal is to lose weight, it's imperative you follow the above macronutrient profile and check your ketone levels.

Ready to give the keto diet a try? Check out this dietitian's beginner meal plan [9].