10 Things to Know Before Trying the Zone Diet

Although Dr. Barry Sears developed the zone diet in the 1980s, one of its main selling points makes it sound like it could have been developed recently: It’s an anti-inflammatory diet that follows a specific macro breakdown. And like many diets, it’s also designed to promote weight loss. But while the zone diet is one of the more balanced and less restrictive eating plans, that doesn’t necessarily mean it’s easy to follow.

Here, 10 things to know before trying the zone diet:

The zone diet recommends about 1,200 total daily calories for women and about 1,500 calories a day for men. Anything less than 1,200 calories would be considered close to starvation for the average adult. Even 1,500 calories, especially for men, would be too low for an active adult,” says nutritionist Keri Gans, RD, author of “The Small Change Diet.” These calories should be divided among three meals and two snacks so you eat frequently.

Each meal and snack should consist of 40% carbs, 30% protein and 30% fat on the zone diet. “If you’re really trying to do this by the book, you need to do the calculations,” Gans says, which you can set and track with an app like MyFitnessPal. However, if you find yourself constantly worrying about the math and what you should be eating to the point where it’s causing additional stress in your life, it might not be the best option for you, notes Mascha Davis, RD.

The diet also advocates using your plate to estimate your macros: Fill 1/3 with lean protein and 2/3 with complex carbohydrates, then add a little healthy fat such as olive oil, avocado or almonds. “Eating should not be confusing, it should be enjoyable. If a diet confuses you, realize it’s another diet you will likely start and eventually stop,” says Gans.

Various fad diets call for totally eliminating carbs, animal products, dairy or other food groups, but that’s not the case with the zone diet. “It includes all basic food groups and instead restricts less-nutritious fare like processed foods,” says Davis.

We all know it’s best to cut back on added sugar and choose whole grains over refined ones. However, the zone diet also considers some fruits and vegetables as “unfavorable” because they are higher on the glycemic index scale. This includes acorn squash, bananas, beets, carrots, peas and sweet potatoes. “You don’t want to blacklist any fruit or vegetable. They all have nutritional benefits,” says Gans. “Plus, if you’re a picky eater and you decide to follow a diet that only includes fruits and veggies you don’t enjoy, then you’re more likely to put less nutritious foods on your plate.”

The zone diet calls for only decaf coffee and tea or, at most, one cup of caffeinated coffee or tea daily. Coffee has been shown to help with athletic performance and for many who have an aversion to decaf, this could make the diet very hard to follow. “I’m not sure why the zone diet discourages coffee, but for some people who enjoy more than a cup a day, it would be a deal-breaker,” Gans says.

A 1,200-calorie diet for a petite, non-active woman and a 1,500-calorie diet for a small, non-active man may be fine, says Gans. But the average person will be hard-pressed to meet all of their daily nutritional needs. “The exclusion of starchy vegetables and a very low carbohydrate intake can result in deficiencies of some minerals and fiber and cause low energy levels,” adds Davis.

“For people who are active — especially those who do endurance training — this diet will be lacking in adequate carbohydrates,” says Gans. This could result in decreased energy and sub-optimal performance such as crashing too early in a race or a training run. Gans recommends active women consume at least 1,600 calories and active men consume at least 2,100 calories, and that all active individuals try to get 50–60% of their daily calories from carbs.

When you’re trying to follow a specific 30-40-30 macro diet, it takes more time to plan, prep and cook meals, says Davis. You’ll need to spend more time in the kitchen, whether it’s learning how to add flavor to basic ingredients like chicken or making big batches of whole grains. Of course, you’ll need to make time to grocery shop, too.

Gans believes most people will lose weight on the zone diet because it’s so calorie-restrictive. However, if you eat too few calories for weight loss and don’t focus on building strength, you could end up in a yo-yo dieting pattern where you gain the weight back again, explains Gans.