With dozens of different diet plans out there, I’m always looking for the best program to fit my goals and priorities. The 40-30-30 diet caught my eye as a tool for a positive lifestyle change, rather than just a trendy crash diet.
What is the 40-30-30 Diet? The 40-30-30 diet is a plan designed around a simple breakdown of calories: 40% carbohydrates, 30% fat, and 30% protein. This calculated balance of nutrients promises to help lower your risks of cancer, diabetes, and heart disease.
With any meal or diet regimen, planning and knowing all the facts is paramount to long term success.
Facets crucial to this plan include selecting lean proteins and healthy fats, and determining what your total caloric intake before diving it amongst these categories.
Everything You Need to Know About the 40-30-30 Diet
The 40-30-30 diet is structured to make your body perform at its maximum ability. It does this by its emphasis on eating the right types of foods in the correct amounts.
Dr. Barry Sears created the Zone Diet over thirty years ago, but it didn’t catch on until the ’90s. The original purpose behind the diet was to “control the body’s production of the hormone insulin”.

One of the things insulin helps with is regulating the storage of extra energy (such as fat) when we eat. The hormone, glucagon, has the opposite job of releasing stored glucose whenever it is needed.
Dr. Sears asserted that through the 40-30-30 diet, you could balance insulin and glucagon by controlling the foods you eat, therefore maintaining a healthy weight as well as a regular bodily function.
The 40-30-30 diet today is all about efficiency and balance. It helps your body reach maximum performance by eating the right types of foods in the correct amounts, specifically your main macronutrients: carbohydrates (40%), fat (30%), and protein (30%).
Not any food will do and the key is about the “right types of food”! Potato chips and beef jerky might help you hit the target numbers, but it doesn’t sound all that healthy. You want to reach the proportions with nutritious food.
The breakdown of 40% carbs, 30% fats, 30% protein is easy to understand and remember. And with some practice, it will eventually become second nature. So will your ability to read food labels.

Best Foods for the 40-30-30 Diet
Let’s get to the good stuff; the food options. What can you eat while on the 40-30-30 diet? What shouldn’t you eat?
Here are a few lists to give you an idea of some of the best foods for each of your macros:
Fats | Carbs | Protein |
---|---|---|
Avocados | Whole Wheat Bread | White-Fleshed Fish |
Eggs | Multigrains | Chicken |
Fatty Fish | Brown Rice | Nuts |
Cottage Cheese | Non-Starchy Vegetables | Low-fat Ground Turkey |
Nuts | Quinoa | Eggs |
Chia Seeds | Bran Cereal | Legumes |
Extra Virgin Olive Oil | Oatmeal | Cottage Cheese |
Coconut Oil | Legumes | Lite Tofu |
Yogurt | Nuts | Powdered Peanut Butter |
As you can see from the chart, some foods are in more than one category. Consider those superfoods.
They give you some flexibility in your food choices. For example, adding cottage cheese as a thickener gives you fats and protein at the same time.
There are plenty of options to put together some delicious meals, but you’ll also see your options for snacking will change.
Rather than grabbing a handful of process chips or cookies, it would help if you went for celery with powdered peanut butter, or a handful of almonds, or a few cherry tomatoes. All of these incremental changes become important.

While you implement those foods, steer clear of:
- Fatty Protein (steak and high-fat meat in general)
- Empty Carbs (dinner rolls, white rice)
- Carbs with High Sugar Contents (potatoes, sweet potatoes, bananas, mangos, dates, and raisins)
- Bad Fats (lard, heavy cream, sour cream, butter, margarine, shortening and fried food in general)
For some great ideas for meals, snacking, and meal prep, check out the Balance Blog.
How the 40-30-30 Diet Can Affect Your Overall Health?
1. Heart Health
According to the American College of Cardiology – in the United States in 2019, coronary events are expected to occur in about 1,055,000 individuals.
To many, those numbers are scary enough to put heart health at the top of the priority list when researching new diets.
This diet, specifically, is a big winner for your heart health. It encourages more vegetables while discouraging things like red meat and unhealthy.
If lowering your risk for heart disease is high on your priority list, this is an excellent plan to rework your daily routines and keep that ticker healthy.

2. Can People With Diabetes Do The 40-30-30 Diet?
The way 40-30-30 is structured makes it a good model for balance and moderation geared down to the core nutrients, rather than blanket statements of caloric moderation like many other diets.
This approach helps to instantly improve your chances to fend off diabetes. According to a study in the British Medical Journal, the 40-30-30 plan is a huge asset to anyone diagnosed as pre-diabetic.
They ran a six-month trial on the 40-30-30 diet for 24 men and women that were pre-diabetic. By the end of strictly sticking to the diet for six months, they saw a 100% remission rate from everyone.
3. Cancer
As much as I wish I could tell you there is a diet to obliterate cancer, I can’t. But there has been ample research on foods that may increase or decrease your chances.

Some of the worst foods for cancer are:
- Red meat
- Alcohol
- Added sugars
- Fried foods
- Refined carbs
The 40-30-30 diet promotes healthy grains over refined carbs, lean meats rather than fatty red meat, and lifestyle changes rather than 30-day quick-fix diet plans.

“What a person has been eating a year before they were diagnosed with breast cancer, for example, probably isn’t as relevant as what they’ve been eating a decade or two before.”
– Randall Oyer
Simply put – a diet like 40-30-30 that encourages positive changes that relate directly to good and bad foods for cancer prevention plus long term changes in your lifestyle that will make a more meaningful impact over time.
For more info on how diet directly relates to cancer, check out Anti-Cancer; a book by Dr. David Servan-Schreiber.
How The 40-30-30 Diet Works?
Okay, so you’re on board with the whole concept of 40-30-30, and the benefits sound amazing.
But what is the most significant part of any meal plan or diet? Sustainability. You need to decide if this is going to fit your lifestyle.
So here is a quick breakdown of what to expect:
- Stage One: Your body is about to undergo some significant changes and you need to give it time to adjust to that. So stage one consists of two weeks for your body to adapt. Consider this your “breaking bad habits” phase.
While the idea of how long it takes to break bad habits is still up for debate, many point to two weeks as an aggressive, but reachable goal.
- Stage Two: Now that you have a grasp on the best and worst foods for the 40-30-30, you can begin customizing meals and having fun with the plan. This will be an exploratory phase where you learn specifically which foods on the plan feel right to you.
(You may refer to the food chart for inspirations)
- Stage Three: When you reach stage three, it means you have hit your goal weight. This diet is about losing some weight in the beginning and then maintaining a healthy and nutritious lifestyle afterward.
If your goal is to lose ample weight, you will need to be diligent about not just your diet, but also implementing a workout regimen to match it. You can also be more wary of your caloric intake while maintaining your 40-30-30 macro breakdown.
How much weight you lose will be dependent on your start weight and body frame, how strict you are with yourself on the diet, and your level of exercise.

How to Calculate the 40-30-30 Diet Plan?
You need to know how many daily calories you should be consuming in total before starting this plan.
Your caloric intake will depend on things like your sex, age, start weight, goal weight, and activity levels. You can find caloric calculators online, such as this one through Healthline.
For example, if you are sticking to a 1500 calorie diet:
- 600 calories from carbs (40%)
- 450 calories from fats (30%)
- 450 calories from proteins (30%)
A common question for this diet is, “How do I know what 40g of carbs is?” Using that formula above will give you the caloric amount you can intake each day. I know “carbs” has become a scary word for dieters, but it doesn’t need to be.
Using a food tracker/calculator will help you stay strict in the amounts you consume for carb-based calories, along with the actual grams of carbs per serving.

The Importance of Diligent Meal Prep
I recently read a story of a couple that lost a combined 200 pounds by doing “extreme meal prep.” Every Sunday they cooked every single meal they would need for the week and would not waver from those pre-made meals.
As someone who forgets their lunch at home most days, this sounded impossible to me.
But if you look at a diet like the 40-30-30, meal prep is the ticket to success. With such specific guidelines, you need to be clear and calculated in your meals.
If you put aside a few hours every Sunday afternoon to prepare for the week ahead, you will see the payoffs later in the week.
Whether you get home late and are feeling too lazy to think about cooking, or you’re tempted to just order-in on a cold rainy day, you have your perfectly balanced meals ready to go.
I think this is the real kicker in deciding if this diet is the one for you. I have a friend who is very purposeful about everything she chooses to eat and maintains a very healthy diet.
But if you asked her to measure and track macronutrients, she would look at you like you’re crazy. This would not be the diet for her.
Instead, this is precisely the diet for someone who enjoys the process of meal prep, the certainty of the numbers behind the formula, and the specificity of its approach. This diet is for planners who want to take the guessing out of where their calories should come from.

Additional Things to Consider
Here are some things to keep in mind regarding the 40-30-30 diet. These are common questions that occasionally come up.
- Is There a Calculator I Can Use? The best way to track your macronutrients so you can stay on the right path is to get a food tracking app. I’ve always liked MyFitnessPal or the Fitbit app if you are an active Fitbit user. Many health and fitness websites will also offer a calculator similar to those apps.
- Will This Be a Good Plan for a Vegetarian? – This is still sustainable for vegetarians who are willing to pack in the protein through plants, nuts, and eggs. Legumes, tofu, and an array of different nuts can help keep your meals fun and fulfilling while hitting your protein goals.
- How much does this Cost? There is no cost to the program itself, but if you wanted to go for a premade route, there are meal delivery services that specifically offer a 40-30-30 option.
- Is the 40-30-30 diet for me? I have a friend who is very purposeful about everything she decides to eat and maintains a very healthy diet. But, if you asked her to measure and track macronutrients, she would look at you like you’re crazy. This would obviously not be the diet for her.
With that said, this diet is ideal for anyone who enjoys the process of meal prep, the certainty of the numbers behind the formula, and the specificity of its approach. 40-30-30 is for planners who want to take the guessing out of where their calories should come from!

Final Thoughts About the 40-30-30 Diet
Although this is not a weight loss diet, nor is it a diet for everyone, you might want to consider it as a way to have a diet that is easy to implement, has enough flexibility to keep your meals interesting, and lets you still eat your favorite foods—as long as it’s not just potato chips and beef jerky.