As an avid traveler and former expat, she enjoys sharing her experiences and tips with other enthusiastic explorers. Nutrition Label. Video of the Day. Step 1. Step 2. Step 3. Step 4. If the second option is true, then maybe what makes us fat is not an energy imbalance but something more akin to a hormonal defect, an idea embraced by European researchers prior to World War II.
If so, the prime suspect or environmental trigger of this defect would be the quantity and quality of the carbohydrates we consume. Under this scenario, one fundamental error we have made in our thinking about obesity is to assume that the energy content of foods—whether avocado, steak, bread or soda—is what makes them fattening, not the effects that these foods, carbohydrates in particular, have on the hormones that regulate fat accumulation.
Given how often researchers refer to obesity as a disorder of the energy balance, one might assume that the concept had been rigorously tested decades ago. But a proper scientific vetting never actually happened. The experiments were too difficult, if not too expensive, to do correctly. And investigators typically thought the answer was obvious—we eat too much—and so the experiments were not worth the effort. As a result, the scientific underpinning of the most critical health issue of our era—the burgeoning rates of obesity and diabetes and their complications—remains very much an open question.
After a decade of studying the science and its history, I am convinced that meaningful progress against obesity will come only if we rethink and rigorously test our understanding of its cause. Last year, with Peter Attia, a former surgeon and cancer researcher, I co-founded a nonprofit organization, the Nutrition Science Initiative NuSI , to address this lack of definitive evidence.
The investigators will follow the evidence wherever it leads. If all works out as planned, we could have unambiguous evidence about the biological cause of obesity in the next half a dozen years.
The Hormone Hypothesis To understand what makes the hormone hypothesis of obesity so intriguing, it helps to grasp where the energy-balance hypothesis falls short. The idea that obesity is caused by consuming more calories than we expend supposedly stems from the first law of thermodynamics, which merely states that energy can neither be created nor destroyed. As applied to biology, it means that energy consumed by an organism has to be either converted to a useful form metabolized , excreted or stored.
Thus, if we take in more calories than we expend or excrete, the excess has to be stored, which means that we get fatter and heavier. So far, so obvious. But this law tells us nothing about why we take in more calories than we expend, nor does it tell us why the excess gets stored as fat. Specifically, why do fat cells accumulate fat molecules to excess? This is a biological question, not a physics one. Why are those fat molecules not metabolized instead to generate energy or heat?
And why do fat cells take up excessive fat in some areas of the body but not others? Saying that they do so because excess calories are consumed is not a meaningful answer. Answering these questions leads to consideration of the role that hormones—insulin, in particular—play in stimulating fat accumulation in different cells. Insulin is secreted in response to a type of carbohydrate called glucose. When the amount of glucose rises in the blood—as happens after eating a carbohydrate-rich meal—the pancreas secretes more insulin, which works to keep the blood glucose level from getting dangerously high.
Insulin tells muscle, organ and even fat cells to take up the glucose and use it for fuel. It also tells fat cells to store fat—including fat from the meal—for later use. So if you eat 6 cookies, you are eating 2 servings, not 1.
To figure out how many calories those 2 servings contain, you must double the calories in 1 serving. Low-fat, reduced-fat, light or lite , and fat-free are common terms you may see on food packages. The U. Low-fat foods may contain 3 grams of fat or less per serving. Foods marked reduced fat and light lite are a little trickier, and you may need to do some investigating. Light lite and reduced-fat foods may still be high in fat. But if the regular version of a particular food was high in fat to begin with, the reduced-fat version may still be high in fat and may have more added sugar.
That's why one food with the same serving size as another may have far more calories. A higher-fat food has many more calories than a food that's low in fat and higher in protein or carbohydrates.
So, the amount of fat in foods can make quite a difference when it comes to total calories in a food. All types of fat have the same amount of calories, but some fats are better than others. They are liquid at room temperature and mostly come from plants. Saturated fat and trans fat raise blood cholesterol levels and increase a person's chance of heart disease.
Saturated and trans fats are solid at room temperature — like butter, lard, and fat on meat. Saturated fats and trans fats are listed on food labels. Water loss during sleep can lead to people weighing less in the morning, while their bodies have also burned calories overnight.
Learn more. Weight loss apps can help people reach their fitness and health goals. Learn more about which weight loss apps are available to download. A recent review investigates the potential health benefits of time-restricted eating. The review examines both animal and human studies. This article explores the Galveston Diet, how it works, what to eat and avoid, the research behind it, and its benefits and drawbacks.
What to know about calories and body fat. Medically reviewed by Natalie Butler, R. How fat works How calories work Losing weight Summary In relation to food and the body, calories are units of energy that allow the body to work. How fat works. Share on Pinterest Having too much or too little body fat can cause health problems. How calories work.
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