The Whole30 Diet: The Cons—And the Main Pro

Whole30 is a 30-day elimination diet that cuts out alcohol, sugar, legumes, grains, dairy, and all processed foods. Followers of the diet have noted weight loss and increased energy along with identification of any problem foods. However, like any ultra-restrictive diet, Whole30 has its downsides.

"While I like the fact that the diet focuses on whole, minimally processed foods such as fruits, vegetables, nuts, and seeds, it eliminates many healthful foods like grains, soy, beans, and lentils," Sharon Palmer, RDN, nutritionist and author of "The Plant-Powered Diet," told Health.

From banning certain superfoods to unnecessarily upping protein intake, Whole30 isn't without flaws. Here, Palmer explained the top five dangers of doing Whole30, plus what the meal plan gets right.

It Might Mess With Digestion

"The science on the health benefits of soy foods and pulses like beans, lentils, dried peas is overwhelming," Palmer said. "They're packed with high-quality nutrients, such as protein, fiber, vitamins, minerals, and phytochemicals." What's more, legumes are great for gut health. Rich in both soluble and insoluble fiber, beans are critical for a healthy gut microbiome, as they help feed the good bacteria in your intestines.

Whole30 bans beans based on the idea that they contain "anti-nutrients" like phytates, which are compounds found in plants that can potentially block the body's absorption of important minerals like magnesium, iron, and calcium. In reality, the health benefits associated with beans far outweigh this potential interaction, and phytates are largely destroyed by food prep methods like sprouting and soaking.

"This is one of my key issues with Whole30," Palmer said. "There is no science to support eliminating these foods."

It Could Actually Induce Food Sensitivities

Once dieters complete Whole30, they enter a "reintroduction" phase during which they add the foods they've avoided for a month back into their diet one by one. The point of this phase is to help people pinpoint the food groups that aren't serving them. For example, if someone eats a bowl of yogurt post-Whole30 and suddenly gets super bloated, it may be a signal that dairy doesn't sit well with them.

However, once you cut foods out of your diet for an extended period of time, it's possible you'll react to them when they're reintroduced—whether you previously had a sensitivity to them or not.

"There is some evidence to show that when you shift your diet, your gut microbiota composition and enzymes shift too," Palmer explained. For example, if you cut out dairy, you may drive down the amount of enzymes you have to digest it. "Our bodies are wonderfully adaptive, but sometimes this has consequences," Palmer added.

It Could Make Cravings Even Worse

Since the Whole30 diet is basically a month-long exercise in avoiding certain foods, you may start wanting all the sweets (or gluten or dairy or wine) that you eliminated while following the strict plan. "When you overly restrict the diet, it can set up unhealthy eating behaviors and attitudes," Palmer explained. "If you feel deprived, the diet encourages you to have a strong desire for 'forbidden' foods." Not only is it no fun to yearn for off-limits eats for an entire month, but it also means you may be more likely to go overboard on them once the program is over.

It Could Heighten Your Risk of Chronic Diseases

Individuals should be getting proteins from animal and plant products, according to the Dietary Guidelines for Americans from the Office of Disease Prevention and Health Promotion (ODPHP). Unlike plant-based protein sources such as beans, soy, and even whole grains, animal proteins like red and processed meats have been linked to a whole host of chronic diseases. "Numerous studies have documented health risks associated with high meat diets, such as increased risk of type 2 diabetes, certain cancers, and heart disease," Palmer said. Thus, swapping out black beans for bacon would not be ideal.

It's Not Sustainable

Whole30 isn't meant to last forever; after all, the program's website does include the line: "It's only 30 days." On the one hand, this one-month focus makes sense; no one should have to ditch grains, legumes, and dairy forever. But Palmer said the 30-day program is problematic as it fails to impart sustainable healthy habits.

"A diet needs to be a way of eating that you can maintain for your whole life," Palmer explained. "It should set you up for a healthful, more vibrant life, not just for a period of time of weight loss."

Since it's pretty much impossible to go through life without ever having bread, pizza, or cookies again, most long-term Whole30-ers end up abandoning the meal plan. Instead of taking an all-or-nothing approach, Palmer recommended simply applying the core principle of Whole30 to your lifestyle whether you've tried the elimination diet or not: Eat more whole, unprocessed foods.

A Quick Review

While there are some beneficial aspects of the Whole30 diet that are good—namely that it promotes minimally processed foods—there are also downsides. Cravings could get out of hand, it can introduce food sensitivities, and ultimately, it's not a sustainable way of eating. If you have any questions about whether Whole30 is right for you, reach out to a registered dietitian or healthcare provider.