Counting calories fails because the body does not treat every calorie the same. Insulin decides whether a calorie is burned for body heat or stored as body fat. Even careful tracking is off by as much as 20 to 50 percent. And the standard calorie-reduction approach gives an obese person a 1 in 167 chance of reaching a normal weight.
Counting calories often fails. Instead, focus on eating real food.
What is a calorie?
In physics, a calorie is the energy needed to raise the temperature of 1 gram of water by 1 °C. The calorie you see on a food package, however, is actually a kilocalorie, or 1,000 calories. That is the energy needed to raise the temperature of 1 kilogram of water 1 degree Celsius. The original method for finding the calories in a food directly measured the energy it produced. The food was placed in a bomb calorimeter, a sealed container surrounded by water. The food was burned completely, and the rise in water temperature was measured.
What is a nutritional calorie?
Calories in food and calories measured in physics are not the same. Nutritional calories leave out the parts we cannot digest (non-digestible components), such as dietary fiber and artificial sweeteners. Both of these could be burned in a bomb calorimeter to make heat. Many of the components humans can’t digest, such as cellulose, are the main energy source for other species. Human calories depend on the body’s ability to catabolize (break down) them. That usually involves enzymatic action rather than a high-temperature oxidation reaction.
Food labeling
Food labels are based on estimating the calories in each food component. The label adds up the calories from the energy-containing nutrients: protein, carbohydrate, fat, and alcohol. Carbohydrates contain some fiber that the body does not digest and use. Because of this, the fiber is usually subtracted from the total carbohydrate before the calories are calculated. The Atwater system uses the average values of 4 Kcal/g for protein, 4 Kcal/g for carbohydrates, 9 Kcal/g for fat, and 7 Kcal/g for alcohol.
http://www.nal.usda.gov/fnic/foodcomp/
http://www.nat.uiuc.edu
These nutritional calories are the energy available in food. Our body can use that energy for chemical reactions or store it in reserve as fat or glycogen. We count the calories the body can extract from the food we eat. But we ignore the interaction of that food as a signaling molecule. We also ignore the non-digestible components and the thermic energy used in breaking the food down.
Nutritional science has a paradox. A high-calorie intake of one food substrate causes weight gain. Yet the same calorie value of another substrate seems to cause weight loss. This leads some to suggest that calories don’t count.
The laws of physics are not broken, however. Calories do matter for energy balance. Whether fat, protein, or carbohydrate, a surplus of calories will lead to weight gain. What matters is the quality of the calorie. It is also the body’s response to those specific nutrients as signaling molecules, beyond their direct calorie value. The body turns food into usable energy through a highly complex process. It starts with the mechanical breakdown of food. Chemical and enzymatic processes follow throughout the gut, and these are significantly affected by the individual microbiome. The body is not static. How it uses a nutrient changes all the time. So does the extraction of energy associated with that nutrient. The real issue in managing obesity and type 2 diabetes is how the body uses the nutrients it is given. It is also whether that specific approach works for that specific person, at that specific time.
Food as a nutrient and as programming:
Food should be viewed as a source of nutrient energy (globally translated as calories). But it is also a set of instructions to the body, a program directing the body to a specific action. Food is not completely broken down to its basic parts during digestion. It keeps components intact, which then program the cells. A corrupted program can lead to outcomes such as obesity or diabetes or even an autoimmune state. These instructions are read not just by the body, but also by the gut microbiome. The microbiome can translate the instructions on its own. It creates its own programming subroutine, which then affects the body. Conventional nutrition advice ignores the program code carried in the food we eat. But these instructions cannot be ignored.
Focusing on what you can’t have only makes you want it more.
It’s easier to track not eating sugars and artificial sugars than to count their calories. Tracking and reliving the calories of carbohydrates you didn’t eat stimulates ghrelin, the hunger hormone.
Instead of calories, focus on real food.
It’s easier to track pounds of steak, fish, shrimp, or chicken than calories. It’s not what you didn’t eat. It’s what you did eat and who you are that matters. You are a person that doesn’t eat sugars (artificial or natural). You don’t fall prey to the big processed food manufacturers. And you know the truth about vegetable oil.
Focus on feeding windows and time-restricted feeding.
It’s easier to track the hours of healthy eating than calories. Say you know that you will only eat in a limited time window of 6 to 8 hours per day. Then the rest of your time becomes available for real activity.
A calorie is a calorie only if it is burned in a bomb calorimeter and the heat given off is measured. Biologically derived calories from different foods have entirely different metabolic effects on the human body. Equal calorie portions of sugar, alcohol, meat or olive oil have widely differing effects on hormonal systems such as insulin. They also differ in their effects on satiety (fullness) signals such as cholecystokinin or peptide YY. It does not matter how many calories a portion of food on a plate contains. What matters is how our body responds to eating and absorbing those calories, and how they are metabolized. It also matters how full we feel as a result, which is called satiety.
The current calorie-reduction strategies promoted for weight loss do not work. The standard calorie-reduction approach gives a 1 in 167 chance of reaching a normal weight. That is a greater than 99% failure rate.
Fildes A et al. Probability of an Obese Person Attaining Normal Body Weight: Cohort Study Using Electronic Health Records. Am J Public Health. 2015;105: e54–e59
It is wrongly assumed that eating too many calories is the root cause of obesity. A calorie of food energy has different metabolic fates depending on the hormonal stimulation. That same calorie may be used to make body heat or be stored as body fat. Obesity is a disease of failed energy partitioning (how energy is divided up), not one of total energy intake. The main driver of this partitioning is the hormone insulin, which is specifically a fat storage growth hormone.
Focusing on calories in and calories out creates a built-in bias against high-fat food. Yet high-fat food may actually protect against obesity and related diseases. The simple calorie focus results in dietary guidelines that support replacing fat with starch and sugar. That swap promotes insulin resistance.
We hope to shift focus away from calories and toward a dietary pattern built on food quality rather than quantity. It is our hope that this shift will reduce obesity, related diseases and cardiovascular risk.
Malhotra A, DiNicolantonio JJ, Capewell S. It is time to stop counting calories, and time instead to promote dietary changes that substantially and rapidly reduce cardiovascular morbidity and mortality. Open Heart 2015;2(1) DOI: 10.1136/openhrt-2015-000273.
Snacking will make you fat because of the chronic high insulin from the constant feeding.
There have been two major changes in our eating habits since the 1970s, before the obesity epidemic began. The change to a high-carbohydrate, low-fat diet has been well documented. It has played an important role in causing obesity. However, the increase in meal frequency plays an equal, if not larger, role. That change has been largely ignored. In the 1970s, the average number of eating opportunities was three: breakfast, lunch and dinner. By 2005, that number had almost doubled. Now we eat breakfast, snack, lunch, snack, dinner, and snack. Each of these contains refined carbohydrates more often than not.
Cameron JD. 6 meals per day do not result in greater weight loss. Br J Nutr. 2010 Apr;103(8):1098-101
Popkin BM. Does hunger and satiety drive eating anymore? Am J Clin Nutr 2010;91:1342–7
Tracking calories to make sure you are eating less is self-deception. Even if you did track calories carefully, you would be off by as much as 20-50 percent. Even if you were perfect at tracking the actual calories, your math wouldn’t account for the bio-availability of nutrients (how much your body can absorb). It also wouldn’t account for the effect of anti-nutrients from vegetables, or the thermic effect of food. Your resting metabolic calorie needs change from day to day, hour to hour, and season to season. Your gut microbiome determines nutrient absorption. It changes all the time and interacts with your enteric nervous system (the nerves of the gut) and central nervous system.
Some people assume that the “calories burned” number on their workout equipment is accurate, but it’s not. Many people also reward themselves with a snack for exercising. That is a bad idea.
Instead of calorie counting:
Practice Hara Hachi bu, a Confucian teaching that instructs people to eat until they are 80 percent full. “Eat until you are eight parts (out of ten) full” or “belly 80 percent full.”
Simple changes to your eating patterns or the environment will dramatically increase the joy of food.
First, eat more slowly. Eating faster results in eating more. Slow down so your body can respond to the cues that tell us we are no longer hungry. You have a hormone called leptin that lets you know you are full. But if you wolf down your food, it doesn’t have enough time to work. So focus on food. Turn off the TV and the computer. If you’re going to eat, just eat.
Second, use small plates and tall, narrow glasses.
Third, cut out all the snacks. People eat from boredom or they eat from chemical signaling. Most of this chemical signaling can be eliminated when you remove artificial flavors, refined sugars, and industrial seed oils.
You probably have the mantra “breakfast is the most important meal of the day” stuck in your head. This was a baseless marketing phrase created in 1944 by General Foods to sell more cereal. John Harvey Kellogg of the Kellogg’s cereal company was a deeply religious Seventh-day Adventist. He believed that cereal would improve Americans’ health and keep them from masturbating and desiring sex. Before the invention of cereal (to reduce masturbation), breakfast was not as standard or routine. Kellogg might actually have been half right. Breakfast didn’t improve health. But eating more often, with processed cereal foods, results in more insulin resistance and worse male impotence.
Cut out breakfast, unless it is one of your two meals of the day and it falls inside your eating window. Regular breakfast consumption increases weight and insulin resistance by adding unnecessary calories to diets. https://doi.org/10.1136/bmj.l42
Eliminate vegetable oil.
One of the easiest swaps you can make is cutting out vegetable oil and replacing it with real fat. Real fat tastes better and makes your food more flavorful. It also carries fat-soluble vitamins.
Bottom line:
If you are eating real food, your willpower is better spent somewhere other than calorie counting and calorie restriction. Remember, you are retraining your body to know when it’s actually full and what real hunger is. Your goal is to eat only when truly hungry.
Cutting out breakfast and eating only in a 6 to 8 hour period each day makes this simple. Get rid of artificial flavorings, artificial and refined sugars, and refined foods. Healthy fat keeps you satiated (full) for a long time. Satiety and the nutrient density of food are the ultimate test.
It’s not what you didn’t eat; it’s what you did eat and who you are that matters. It’s more about how your body responded to the food you did eat.
Reframe who you are:
You are a person that doesn’t eat sugars (artificial or natural). You don’t fall prey to the big processed food manufacturers. And you know the truth about vegetable oil.
Frequently asked questions
Can I lose weight by just counting calories?
Rarely. The standard calorie-reduction approach gives an obese person a 1 in 167 chance of reaching a normal weight. That is a failure rate above 99 percent. Calories do count. But insulin decides whether a calorie is burned for body heat or stored as body fat. And even careful tracking is off by as much as 20 to 50 percent.
Should I count calories or just eat healthy?
Eat real food and stop counting. It is easier to track pounds of steak, fish, shrimp or chicken than calories. It is easier still to track hours. Eat only within a 6- to 8-hour window, cut out snacks, and drop sugars, artificial flavorings, refined foods and vegetable oil. Healthy fat keeps you full for a long time, so you eat only when truly hungry.
Why am I not losing weight eating 1500 calories a day?
Because the number on your tracker is not what your body does with the food. Counts run 20 to 50 percent off. They ignore how food signals your hormones. And your resting calorie needs change from day to day. Snacking keeps insulin high, and high insulin sends calories into fat storage. Workout machines overstate calories burned, and a reward snack after exercise undoes the effort.
Related reading
- Nutritional Ketosis and Time-Restricted Feeding
- The Calorie Paradox: Why Counting Calories Fails
- The Secret to a Healthy Weight: Insulin, Not Calories
Sources
- Fildes A, Charlton J, Rudisill C, et al. Probability of an obese person attaining normal body weight: cohort study using electronic health records. American Journal of Public Health. 2015. PMID 26180980
- Ludwig DS, Ebbeling CB. The carbohydrate-insulin model of obesity: beyond “calories in, calories out.” JAMA Internal Medicine. 2018. PMID 29971406
- Ebbeling CB, Feldman HA, Klein GL, et al. Effects of a low carbohydrate diet on energy expenditure during weight loss maintenance: randomized trial. BMJ. 2018. PMID 30429127
Medically reviewed by Dr. Gurpreet Singh Padda, MD, MBA, MHP
Interventional pain physician, addiction medicine specialist and obesity medicine diplomate.
Licensed in Missouri and Illinois.
Last reviewed August 31, 2026
