What You Should Know Before Trying a Ketogenic Diet
Five people have recently told me they were going to “try keto”—the most recent after gushing about a mutual friend who has been doing keto, aka the popular ketogenic diet, and getting awesome-looking results. You’ve probably heard rumblings about keto, but what the heck is it? And is it too good to be true?
Let’s first get you caught up on all the hubbub around the ketogenic diet. Keto is an extremely low-carb, moderate-protein, and high-fat diet. You’ll find those on keto gobbling up stuff like fat slabs of bacon, mountains of avocados, and cartons of heavy whipping cream. There’s a lot of enthusiastic fanfare around it, like this comment on Reddit:
Awesome. And then there’s this one:
Low-carb diets are nothing new for weight loss. And keto is kind of a low-carb diet with a twist in that you emphasize tons of fat. I spoke to Leigh Peele, NASM certified personal trainer who fields questions on all matters of weight loss, metabolism, and nutrition, and is author of Starve Mode; and she told me that the original definition of keto is a 4:1 ratio of fats to carbohydrates or protein. That is, for every gram of protein or carb you eat, you would also eat four grams of fat (hence, the avocados and heavy whipping cream). But you don’t have to stick to that exactly as long as your carbs are low and protein moderate enough to properly be “ketogenic.”
Let me explain.
Differences Between Keto and a Low-Carb Diet
Keto’s trump card against the average low-carb diet is that, after consistently depriving yourself of bread, pasta, donuts, and any carb source, your body goes into ketosis (between a couple of days and a week). Ketosis means your body is breaking down fat and releasing large quantities of molecules called ketones into your bloodstream. Your body then uses these ketones as its primary fuel source since you’ve severely limited the body’s preferred energy source: carbs.
Just how few carbs do you need to hit ketosis? Typically less than 50 grams of net carbs per day. That’s barely a regular deli bagel. And that’s assuming you don’t have any other “hidden” carbs from particularly starchy veggies or sugary sauces, for example. However, your personal “ketosis threshold” varies. You could enter ketosis with as few as 20 grams or as much as 100 grams. The only way to really tell whether you’re in ketosis is to check via various testing methods (which each has its own problems with accuracy). The easiest to start with are urine test strips.
Does Ketosis Work?
We’re not really certain about its long-term effects on weight loss specifically. The diet has been used as a medical intervention to help reduce seizures in children with epilepsy that don’t respond well to medication, and it’s been shown to have some success. There’s also some evidence that the diet can help improve blood sugar control for people with type 2 diabetes, but Peele stresses that it is not an automatic fix for blood sugar problems.
We’ve heard plenty of hearsay and stories of short-term benefits on weight loss when people drastically reduce their carbs, but it’s not solely because they went all Texas Chainsaw Massacre on any and all carbs. A review of these studies published in American Journal of Clinical Nutrition found that there was no evidence that carbs (or lack thereof) were the one true thing that stood in the way of you and the bangin’ body of your dreams. In fact, there’s a lot we don’t understand about the diet’s mechanisms. That includes keto.