Are some calories worse than others?

Energy is a word with positive vibes. We’d all like to be brimming with energy, to rise every morning full of vigor.

A calorie is no more than a unit of energy, yet its undertone is much less positive.

Calories became the enemy only once we started to have too many of them – as tempting food became abundant and cheap excess calories became the most critical nutrition problem of our time.

All food has calories, which are the energy coin that our body uses for all its processes, and all living organisms run on energy and can’t do without it. The makers of fast and snack foods often argue that a calorie is a calorie, take in more energy than you expend and you’ll gain weight, and thus increase your risk of heart disease and type 2 diabetes.

But although all calories store exactly the same amount of energy, just counting calories doesn’t tell the whole weight gain and weight loss story, and definitely not the wellness story, because we don’t eat calories the way a car fuels with gas. We are complex organisms that eat food, not just for energy, and 200 calories from a kale salad with beets, topped with a sprinkle of nuts and a tahini dressing has a different metabolic effect from the same 200 calories derived from a large cup of soda. The salad is nutritious and leads to greater satiety, and since ours is not a gas tank that senses when it’s full, the intricate mechanisms that signal us to eat may totally ignore the 200 calories from soda.

A group of experts met to discuss whether certain dietary components increase the risk of cardio-metabolic disease beyond extra calories and weight gain. The summary of the conference was just published in Obesity Reviews.

Are calories from sugar worse than calories from other food? 

Kimber Stanhope and Jean‐Marc Schwarz reviewed the evidence linking sugar and cardio-metabolic disease. The discussion doesn’t pertain to the sugars that occur naturally in fruits and vegetables – fruit and veggie consumption is associated with lower risk of heart disease, diabetes and obesity.

On the other hand, added sugar has been linked with unfavorable outcomes.

Several recent meta-analysis of prospective studies consistently linked sugary drinks with heart disease, type 2 diabetes and high blood pressure. The scientific evidence has been reviewed by the Nutrition and Chronic Diseases Expert Group, which concluded that sugary drinks cause heart disease and type 2 diabetes directly and independently from the weight gain they usually cause.

In other words, even if you don’t consume extra calories, and don’t gain weight, there are metabolic downsides to consuming soda and sugary drinks.

While the evidence about sugary drinks is pretty conclusive, added sugar in the solid diet has been less studied, the results are less conclusive, and this is an area in which the authors urge more research.

Another interesting topic is the study of specific sugars. Most sugars in use are a combination of glucose and fructose. Fructose has been shown to dys-regulate metabolism more than glucose, as fructose is metabolized in the liver, overloads it, and increases liver fat. But in all practicality, since table sugar (sucrose), honey, high fructose corn syrup, agave, and pretty much all caloric sweeteners contain fructose, the bottom line is that added sugar poses metabolic risk, beyond its caloric count.

Does a high added sugar diet promote weight gain – in other words, does sugar pack on extra fat beyond what we’d expect from counting the calories?

The authors presented evidence suggesting that certain dietary patterns – namely, the high-sugar, high-fat highly palatable Western, highly processed diet – have the potential to promote weight gain. Refined carbs, i.e. added sugars, may affect some people who are susceptible to them, and have lower glucose tolerance, more than others.

Bottom line

Sugar calories aren’t just empty of any nutrients; excessive amounts of them, especially in liquid form, can cause chronic diseases and metabolic mayhem. That’s why current guidelines urge us to limit calories from added sugar to no more than 10 percent of daily intake, and emphasize minimizing sugary drinks.

Dr. Ayala