Unless you’ve been living under a rock for the past year, you’ve no doubt heard about a friend, coworker, or family member going on the keto diet. The ketogenic, or simply keto, diet is now being accommodated by restaurants, cook books, and touted by every celebrity from Megan Fox to Halle Berry.

This low to zero carbohydrate diet puts the body in ketosis, a process that prompts the body to torch fat vs. carbs by sticking to a diet rich in meat, fish, cheese, eggs, poultry, dairy, and fats while avoiding any high carb foods, like legumes, breads, pasta, potatoes, carrots, and of course, any foods with added sugar. The ideal keto diet consists of only 5% carbohydrates, 20% protein, and 75% fats. However, while keto may result in some weight lost, there are well known pros and cons behind any diet, as any health care provider will tell you. So before you go keto, consider both the negatives and benefits:

1. Aids epilepsy

The keto diet didn’t spring out of nowhere. In fact, it’s been long recommended to epileptic patients to reduce seizures. In fact, doctors at New York’s Stony Brook University, also recommend keto for women with polycystic ovarian syndrome (to improve hormonal regulation) and for patients with diabetes (to manage blood sugar levels).

2. Beware of possible heart impacts

We’ve long been told by doctors that diets rich in red meats and saturated fats leave us at risk for cardiovascular issues (i.e., heightened cholesterol, clogged arteries, and heart disease). It’s true that the recommended foods for most keto diet plans are animal proteins, which are high in saturated fats and LDL (bad) cholesterol.

3. Keto flu

Doctors from New York’s Manhattan Cardiology claim the keto flu is a common side effect of the keto diet. In fact, symptoms of nausea, mood swings, brain fog, headache, and lack of energy are very common in the early stages (or during detox) of keto dieting as individuals gradually withdrawal from caffeine and sugar. However, this so called flu typically subsides within a few weeks.

4. Potential kidney damage

Many registered dietitians will admit that even though there are short term weight loss successes with keto, the trade off for dieters is side effects such as fatigue, nausea, constipation as well as opening yourself up to nutritional deficiencies and a possibility of kidney damage.

5. You’ll probably lose weight

Even though fans of the ketogenic diet will be glad to share their success stories, there are health concerns surrounding a diet that’s so restrictive and that is able to result in rapid weight loss over a relatively short period of time. So even though you may know some folks who’ve lost weight on keto, you should be closely monitored by a doctor while on this diet.