As more people look to reverse quarantine weight gain, I’ve gotten a lot of questions about going keto. Going “keto” essentially means adopting what’s now known as the “ketogenic” diet. Whether you’re trying to lose weight or improve your health, you’ve likely heard of the keto diet. You’ve probably also heard some amazing stories where people have lost as much as 1-2 pounds a day following it.

Despite the almost guaranteed weight loss you’ll achieve, switching to the ketogenic diet can come with some real drawbacks.

Back in 2013, I vetted a ketogenic-inspired, Mediterranean-style diet called the Tisanoreica Diet which was then widely popular in Italy. After shedding a whopping 10 pounds in a week, I was singing keto praises. In fact, the ketogenic diet became my go-to solution for shedding stubborn pounds before photoshoots, vacations, and such.

But let me pause for a moment here. I must warn you not to take my words at face value and go jumping on the keto bandwagon. As a healthy living expert, coach and athlete, I’m always mixing it up and trying new things to recommend (or not recommend) to others. Despite the almost guaranteed weight loss you’ll achieve, switching to the ketogenic diet can come with some real drawbacks.

So, before you even think about trying it, here’s what you need to know.

Basics of the Ketogenic Diet

The ketogenic diet is a low-carbohydrate (or low-carb) diet characterized by a high intake of fat with moderate protein consumption. As its name implies, this diet is specifically designed to activate a metabolic process called “ketosis”. Ketosis increases the body’s inherent fat burning potential, which dramatically supports weight loss, even without counting or restricting calories.

The ketogenic diet is a low-carbohydrate (or low-carb) diet characterized by a high intake of fat with moderate protein consumption.

There’s actually not a ton of ‘newness’ to the ketogenic diet. Ketosis is largely driven by general reductions in carbohydrate intake. This is the basic premise of Paleo and Atkins style diets; though each can be distinguished by the relative composition of fat and protein allowed. Atkins, for instance, is a low-carb, high-fat, high-protein diet while Paleo is a high-fat, moderate-protein diet in which grain and dairy foods are completely withheld.

All these diets involve some level of ketosis resultant from restricted carbohydrate consumption. The lower the carb intake, the more dramatic the weight loss outcome.

How the Ketogenic Diet Works

Simply put, the ketogenic diet kicks fat burning into high gear! Let me break this down a tad bit further.

Under normal conditions, the body preferentially burns glucose to meet its energy demands. Also referred to as blood sugar, glucose primarily comes from the breaking down of carbohydrate-containing foods. If no carbohydrates are available from foodstuffs, the body will instead break down and utilize stored glucose (or glycogen), which is housed in muscle and liver cells.

Now, the body can only store so much energy as glycogen (roughly about 2,000 calories worth). When there’s increased demand, the body taps its fat stores, especially the visceral fat stores situated in the midsection.

This is how ketosis is initiated.

The ketogenic diet kicks fat burning into high gear!

And, if you’re trying to lose weight, this will really work to your advantage.

During ketosis, the body transforms into a fat burning machine. Stored fat is mobilized into the bloodstream and transported to the liver. In the liver the fat is broken down into free fatty acids that are ultimately used to produce glucose. This process also leads to the production of ketone bodies (or ketones) which then serve as an alternative fuel source.

Since the ketogenic diet facilitates the utilization of free fatty acids and ketones for energy, weight loss is greatly maximized. But, remember, the extent of weight loss is largely driven by the presence (or absence) of dietary carbohydrates. Additionally, many other factors can directly (and indirectly) influence ketosis. Such factors include age and gender, health status, diet quality, and even underlying stress levels.

Since the ketogenic diet facilitates the utilization of free fatty acids and ketones for energy, weight loss is greatly maximized.

What The Ketogenic Diet Looks Like

As I mentioned before, the ketogenic diet is a low-carb, high-fat, moderate-protein diet. So you’ll be loading up on foods rich in high-quality fats and protein while keeping your carbohydrate intake very low. By “very low” I mean at or around 20-50 grams of net carbs per day.

Net carbs essentially refers to the total number of carbs absorbed by the body. This is estimated by subtracting the amount of fiber and sugar alcohols in a food from its total carb count.

Foods That ARE NOT Allowed

To successfully initiate ketosis, you’ll pretty much have to eliminate any foods containing moderate-to-high levels of carbohydrates. The obvious ones include overly processed and refined foodstuffs like candies, pastries, desserts, white bread, cereals, soft drinks, most alcohol, and all junk foods.

But many high-quality carbs like whole grains, legumes (beans, peas, and lentils), starchy vegetables and most fruits must also go. While these foods are incredibly nutritious, the sheer presence of starch and/or sugars can really drive up their carb counts. For instance, a cup of cooked beans houses an average of 35 grams of carbohydrates while a medium banana contains about 27 grams.

In addition to carb-rich foods, there are many carb-free foods included on the keto ‘do not eat list’. These include high-sodium foods like smoked, cured or otherwise processed meats, salted nuts and seeds, trans fats, and even refined vegetable oils (sunflower, canola, and soybean oils). And, though technically a valuable source of protein, milk is also not allowed due to the lactose (milk sugar) it contains.

Foods That ARE Allowed

Fish and seafood, meats, poultry, eggs, and non-starchy vegetables like leafy greens, peppers and root veggies are the foundation of the ketogenic diet. Expect to eat a whole lot of these. Plant-based options like nuts and seeds, full-fat tofu and tempeh are also fair game. With the exception of milk, full-fat dairy foods like cheese, sour cream and heavy cream are also allowed.

Only a select few fruits can be included in the ketogenic diet. These include berries, tomato, and savory varieties like avocado and olives. For sweetness, you can use zero-calorie sweeteners like stevia, erythritol, and xylitol. You can even enjoy a little unsweetened dark chocolate on occasion. When it comes to beverages, water, unsweetened teas and coffees, nut milks, hard liquor (without additives), and dry wines can all be consumed.

That’s pretty much it!

The Benefits of Going Keto

There are a lot of upsides to following the ketogenic diet. The obvious one is weight loss. In addition to the increased fat burning potential associated with ketosis, the ketone bodies produced inherently suppress appetite making it a whole lot easier to eat less. This is especially beneficial, as feeling hungry is one of the main reasons people tend to break away from diets.

Going keto is also one of the most effective ways to control blood sugar levels. This helps reduce the body’s reliance on insulin. In addition to supporting weight loss, blood sugar and insulin regulation is especially beneficial in the prevention of diabetes.

And, interestingly, although regular consumption of dietary cholesterol, saturated fat and other nutritional boogeymen are at the heart of the keto diet, it supports a more favorable cholesterol profile by boosting high-density lipoprotein (HDL or “good”) cholesterol and lowering blood triglyceride (fat) levels. This, in turn, reduces the risk of heart disease and potentially life-threatening complications like heart attack and stroke.

There are a lot of upsides to following the ketogenic diet. The obvious one is weight loss.

While this might seem surprising, despite widespread belief, dietary cholesterol and saturated fats contribute very little, if any, to the development of high cholesterol, heart disease, and related health problems. Truth is, day-to-day consumption of foods comprised of trans fats, empty carbohydrates and added sugar is much more of a contributor to chronic disease and overall poor health.

In addition to weight loss and chronic disease-fighting benefits, ketogenic style diets have long been used as medicinal interventions for people with epilepsy (especially children). This is because elevated levels of ketone bodies in the bloodstream can reduce the occurrence of epileptic seizures.

The Downsides of Going Keto

The primary downside of the ketogenic diet is the increased likelihood of weight regain when carbohydrate intake resumes. And, it will likely resume because you’ll more than likely have a slip and fall off the bandwagon at some point. In fact, weight regain is quite common within six months to three years following ketosis-driven weight loss.

You might be able to avoid extreme weight regain with a gradual but limited reintroduction of carbohydrates into your diet from time-to-time, both during and after weight loss. But, honestly, doing so is in and of itself a skill and I’ve found that most everyday folks simply don’t have the knowledge or wherewithal to do it right.

Following the ketogenic diet can often lead to extreme fatigue as well. This can be a real problem if you regularly participate in moderate-to-vigorous endurance exercise. Personally, this is why I always fall off the bandwagon with very low-carb diets in general. For many, fatigue is most pronounced within the first couple of weeks but it could occur more regularly.

The primary downside of the ketogenic diet is the increased likelihood of weight regain when carbohydrate intake resumes.

Another side effect that’s minor but rather unpleasant is halitosis (bad breath). This is caused by high concentrations of ketone bodies. Regularly consuming wheat grass juice, liquid chlorophyll-enhanced water and peppermint tea are just a few strategies I’ve personally used to counter bad breath during ketosis.

For some, this diet could pose more serious health risks linked to micronutrient and fiber deficiencies.

Over time, ketosis could cause kidney problems in individuals with pre-existing kidney disease. It could also increase the risk of kidney failure in individuals with uncontrolled diabetes and other metabolic disorders due to excess excretion of ketone bodies in the urine.

The Net-Net

At the end of the day, the ketogenic diet is not for everyone. So, you should really consider all the factors I’ve highlighted before attempting this diet.

While initiating ketosis is a highly effective strategy for short-term weight loss, weight regain will likely occur unless carbohydrate intake is severely limited or eliminated, indefinitely. And, since the long-term effects of going keto aren’t known, its usefulness for weight maintenance is quite sketchy. As such, if you’re prone to weight gain, initiate this diet with extreme caution and preferably under medical supervision.

Truth is, most people just consume way too many carbs all the time. Therefore, I generally recommend limiting intake to 50-100 grams a day for weight loss and then upping intake to 100-150 grams for long-term weight maintenance. Sometimes it’s about moderation as opposed to elimination.