Making dietary changes can certainly change your health for the better, but in a landscape of ever-changing advice from influencers and other so-called experts, mixed messages and lack of research-backed claims can do more harm than good. Here are four signs you might be taking your diet “improvements” a bit too far, plus five diets that easily qualify as overly strict.

All or Nothing

A big mistake people often make when making diet changes is biting off more than they can chew. It’s all too easy to get wrapped up in a full diet overhaul, which, as most people learn very quickly, is impossible to maintain long term. Instead, set short-term goals and adopt smaller changes you can build upon. A series of small successes can add up to more effective and sustainable changes.

Plant-Based or Bust

There is a huge movement toward more plant-based diets, and the messaging around plant-based eating seems to be getting cloudy. Eating more plant foods like fruits, vegetables, grains, nuts and legumes could increase your intake of several healthy nutrients including fiber, healthy carbs, healthy fats and antioxidants. But this doesn’t require an all-or-nothing approach (see above). Somewhere along the way, the “plants are good” message has sparked a new message that animal foods are bad, which is just plain false.

Eating a vegan diet has been linked to several health benefits including better gut health, weight loss and improved insulin control for those with diabetes; but vegan dieters also run the risk of missing out on important essential nutrients like vitamin B-12, protein, iron and vitamin D. Vegan diets can also be hard to stick to, especially if you’re a picky eater. Plus, if your style of vegan diet is nothing but coconut oil and French fries, it’s unlikely you will see any health improvements. All kinds of foods, both plant and animal, can fit into a healthy diet, so it’s great to increase your plant intake, but there’s no need to necessarily cut out the low-fat dairy, eggs and lean meats.

Cutting Out Entire Food Groups

Speaking of cutting out, any diet that slashes entire food groups from existence should be a red flag. Long lists of foods that are off-limits or demonizing, and slashing an entire macronutrient category just makes eating too hard. Eating in this strict fashion long-term can put you at risk for nutrient deficiencies. While some medical conditions may call for a hiatus from specific foods (like celiac disease, for example), there is good reason to be cautious when unqualified experts call them bad without research-based evidence to back a claim up.

Obsessing Over Everything You Eat

Is your diet a comfortable lifestyle or an unhealthy obsession? Making food choices shouldn’t be stressful or overly time consuming. Consider taking a more mindful approach to eating and your body and mind will benefit. Eat slowly, enjoy your food, pause to ask if you’re hungry or bored before a late-night snack instead of obsessing about how many almonds you ate for a snack today.

What Are the Strictest Diets?

Here are five examples of what not to do when trying to manage weight.

Keto: This glorified low-carb diet is insanely restrictive and poses serious health risks if followed for extended periods of time. Activities like social outings and exercise might be challenging and it’s next to impossible to meet your needs for fiber and other important nutrients.

OMAD: A variation of intermittent fasting which only allows “one meal a day” (hence the acronym OMAD). Cramming all your calories and nutrients into one meal is as difficult and unhealthy as it sounds.

Carnivore: This meat-heavy, low-carb and uber high-protein diet is also packed with plenty of unhealthy saturated fat. Banning all plant foods is also a recipe for several nutrient deficiencies and slew of related health issues that can impact brain, bone and gut health from a lack of healthy fats, calcium and probiotics.

Military Diet: Whether you chose the traditional or vegan version of this wacky diet, this plan makes unrealistic promises of major weight loss in a short period of time. Eating small amounts of obscure foods, even for a few days can be an effective way to lose muscle mass and tank your energy levels.

SlimFast: Any child of the 1980s will attest, this diet is old school restrictive dieting at its best. Eating one “sensible” meal a day and guzzling packaged shakes and low-calorie, low-flavor snacks the rest of the day does not support healthy eating habits or teach dieters anything useful about healthy habits for the long haul.

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