How high is the quality of your diet? Do you think more about the number of calories you’re eating or on the nutritional content of what you’re putting in your mouth? For years, people have focused on calorie counting as a way to lose weight. Their reasoning? If you know how many calories your body needs to maintain your current weight, you can adjust your diet so you’re eating fewer calories. Alternatively, you can burn more calories through exercise. Voila! The weight comes off – or so you might think.
In reality, it’s more complicated than that. Your body makes subtle adjustments based on the calorie content and the quality of what you eat. Otherwise, no one would ever reach a plateau. In response to calorie restriction, your body adapts by slowing your metabolic rate. Appetite hormones like leptin and ghrelin are also impacted so you feel hungrier. That’s why calorie reduction alone isn’t a good long-term formula for weight loss.
The Importance of Diet Quality for Weight Loss and Reducing Calories
Why is diet quality so important? What you eat and drink creates a metabolic environment that helps or hinders weight loss- independent of calorie intake. Of course, you can’t ignore calories entirely, but calorie reduction without changing the quality of your diet will ultimately slow your weight loss and make it hard to maintain the weight you do lose. You’ve probably heard about people who lost weight on a fast food diet, eating Big Macs every day. They’re able to lose weight, at least initially, by controlling their total calorie intake, but what’s the long-term outcome? Probably not very favorable. Chances are they slowly gained back whatever they managed to lose and more. Plus, how does such a diet impact health?
Diet quality matters. Researchers placed two groups of rats on a diet. One group ate a high-glycemic diet consisting of carbs that induced a rapid glucose and insulin response. The other ate a low-glycemic diet. The rats that ate the high-glycemic diet had high insulin levels and increased expression of enzymes that store fat. Furthermore, when they restricted the number of calories the rats on the high-glycemic diet got, they still gained body fat. In fact, they gained almost 70% more body fat relative to the rats that ate a low-glycemic diet.
What does this mean? A diet of French fries, cookies and soft drinks creates an environment that’s ripe for fat storage independent of how many calories you’re eating. Plus, it’s pretty hard to eat low calorie when you’re eating energy-dense foods. High-glycemic foods, like most processed foods, raise your blood sugar quickly and flood your bloodstream with insulin. Insulin turns on hormones that store body fat and turns off ones that break it down. When your blood sugar rises quickly in response to high-glycemic carbs, it falls just as rapidly, leading to increased hunger. You’ll feel hungrier after eating 300 calories of processed carbs than you will 300 calories of a whole grain carb or vegetable.
What happens when you replace high-glycemic carbohydrates with fiber-rich carbs, lean protein, and healthy fats? Your blood sugar rises more slowly and your insulin response is smaller. Insulin levels don’t stay high as long. As a result, your hunger is controlled longer and there’s less of a stimulus to store fat.
Carbohydrates versus Fats: Fat’s Not the Enemy
For years, dieticians and nutritionists recommended low-fat diets to clients based on the idea that fat is more calorie dense than carbohydrates and fat. Unfortunately, this doesn’t always lead to the expected result. People feel hungrier on such a diet and end up eating more. It’s another example of why calorie quality is more important than quantity.
There are metabolic effects as well. In one study, eating a diet low in carbs but high in fat (60% fat) led to an increase in energy expenditure of 325 kilocalories per day compared to a low-fat diet (20% fat). That’s significant! You may consume more calories when you eat a diet higher in fat but you expend more energy. Research shows high-fat diets boost the levels of enzymes that oxidize fat whereas diets high in processed carbohydrates and high-glycemic carbs have the opposite effect.
Other Effects of a Poor Quality Diet
Not only does a diet heavy in high-glycemic carbohydrates make it harder to lose weight and maintain it – it contributes to health problems like insulin resistance and heart disease. If your overall goal is to lose weight AND get healthy, focus on diet quality. That doesn’t mean you should ignore the calorie issue. Eat too much of any food and you’ll put on weight. It’s pretty hard to eat too much of certain foods, especially vegetables.
When you choose foods that are high in fiber and have a high water content like vegetables, you can eat substantial amounts without consuming too many calories. Combine these with lean protein sources for even greater satiety. Despite their higher calorie content, healthy fats from sources like nuts, seeds, olive oil, and fatty fish create a fat-burning environment that helps with weight loss and weight control.
The Bottom Line
Calories still count but focus more on improving the quality of your diet. That’s true whether you’re trying to lose weight or simply maintain. Make low-glycemic carbs, lean protein, and healthy fats the foundation of your diet and limit high-glycemic carbs. When choosing carbohydrates, make sure they’re unprocessed and higher in fiber. Fiber helps to reduce the glycemic response – and it’s good for your health. Don’t be too fixated on counting each calorie. Focus more on diet quality. It’s better for your health and, ultimately, better for your body composition.
References:
Journal of the American Medical Association. Volume 311, Number 21. June 4, 2014.
PLOS One. 2013: 8(3): e58172.
JAMA. 2002: 287(18): 2414-2423.
Related Articles By Cathe:
5 Things That Happen When You Drastically Cut Calories
5 Reasons to Ditch Restrictive Dieting
A New Study Looks at Whether Dieting Slows Your Metabolism
Dieting to Lose Weight May Endanger Bone Health
