This Is Why You’re Fat

Medically Reviewed by Christine Mikstas, RD, LD on March 23, 2023
4 min read

Some find it funny. Others think it’s offensive. Whatever your opinion of the title of fitness expert Jackie Warner’s book, it is definitely intriguing.

In This Is Why You’re Fat, the gym owner and TV personality says her plan will help you get “hot and healthy” without feeling deprived. Warner claims that by ditching sugar, caffeine, highly processed foods, fatty meats, and alcohol and replacing them with healthy foods, you’ll help correct your body chemistry, satisfy hunger, and reduce cravings.

Despite its harsh-sounding title, the book takes a moderate approach to weight loss, promoting what's often called "clean eating," or eating foods as close to their natural state as possible.

You spend the first 2 weeks in the "jump start” phase. During that time, you won’t eliminate anything from your diet. Instead, you help your body get in “fat-burning mode” by adding certain foods, including two eggs, 1 cup of oatmeal, 2 to 3 cups of vegetables, whey protein shakes, and lots of lemon water and herbal tea.

In the diet's second phase, which you can stay on forever, you eat minimally processed or unprocessed healthy foods Monday through Friday as well as most of Saturday and Sunday, and enjoy two treat meals of your choice on weekends -- they shouldn't exceed 1,500 calories.

You eat lean protein (like turkey breasts, eggs, and beans) at every meal. You’ll also eat at least 2 cups of vegetables daily, as well as two pieces of fruit, two servings of whole grains, and small amounts of plant-based fats like safflower oil.

Warner recommends avoiding white flour, sugar, and artificial sweeteners; minimizing caffeine; and avoiding alcohol 5 days a week, due to the calories in alcohol.

Limitations: You'll be avoiding processed foods most of the time, which could be an adjustment.

Cooking and shopping: You’ll be avoiding packaged and processed foods, so plan to shop for and cook your meals. Warner recommends choosing organic food whenever possible. The book includes a list of foods to focus on, practical tips for when you're eating out, and a lot of recipes.

Packaged foods or meals: None recommended.

In-person meetings: No.

Exercise:Exercise is a must on this plan, which includes intervals (varying your pace during a cardio workout) and strength training. If you’re new to interval exercise or strength training, Warner’s short but intense workouts may be challenging.

Vegetarian or vegan: The diet doesn't give specific modifications for vegetarian or vegan diets. But the plan suggests eating plant-based protein sources such as beans, so you could adapt it to meet your needs.

Low-fat diet: You can have small amounts of plant-based fats like olive oil and avocado. Most recipes are low in fat.

Gluten-free: The good-for-you carbs on this diet include some gluten-free options, like quinoa, so the plan should be easy to follow if you don’t eat gluten.

Cost: You don’t need a gym membership to do the workouts that Warner recommends, but you will need a pair of free weights. She also recommends taking several supplements -- including a multivitamin, omega-3 fatty acids, vitamin C, free-form amino acids, and creatine -- which would add to your costs.

Support: This is a plan you’ll do on your own.

Does It Work?

Eating three healthy meals daily along with two snacks totaling 1,500-1,800 calories daily will help most people lose weight. The exercise will also help with that.

Flexibility on the weekends may help you stick to the plan.

Enjoying a clean, balanced diet of lean protein, fruits, vegetables, and whole grains is good advice to feel full on fewer calories. But the scientific evidence on fat-burning foods and associations between hormones, organs, detoxification, liver flushes, and more is weak and unsubstantiated.

Is It Good for Certain Conditions?

You shouldn't add two eggs a day if you have heart disease, diabetes, high blood pressure, or elevated cholesterol levels.

Check with your doctor before starting on this diet plan.

The Final Word

The reason most people get fat is because as they get older, they eat more calories than they need and don’t usually get enough exercise. Not, as the author says, because of how the wrong foods alter your body chemistry.

Forget the oversimplification of the science behind hormones, body chemistry, detoxification, and more. Use the basic diet as a template for healthier eating. Don’t expect miracles or flawless skin.

The real golden nugget is the detailed fitness advice. Use the illustrations and well-designed exercise plans to help you get the best results from your workouts.

The menus, meal plans, and recipes are easy to follow. They're helpful if you like structured meal plans. You can add low-fat dairy to get the calcium and vitamin D your body needs.