Now more than ever, cutting carbs is the first thing many people do when embarking on a weight-loss plan. But does this strategy work? And, does it matter what kind of carbs you take in?
3 Claims for Why Low-Carb Works (And, Are They True?)
There is no common consensus as to why a low-carb eating plan can help with weight loss. Here is a quick-and-dirty summary for why some claim that low-carb eating can help you shed pounds:
1. Carbohydrates trigger insulin to enhance your body’s fat-storing ability.
During digestion, carbohydrates are absorbed into the bloodstream as glucose (aka blood sugar). In response, your pancreas produces insulin, a hormone that opens the door to your body’s cells, allowing glucose to get inside. This is important because your body tissues and organs (especially your brain!) use glucose for fuel. Insulin is stimulated by the food we eat in varying degrees, and carbohydrates stimulate insulin more than any other macronutrient. Protein stimulates insulin to a lesser extent, but fat doesn’t stimulate insulin at all.
What does this mean for weight loss? The release of insulin after a high-carb meal signals a shutdown of fat burning while the body uses the glucose from the carbohydrates for energy. This mechanism is what fuels the low-carb debate. Except there’s one problem. The notion that stimulating less insulin so you can burn fat doesn’t pan out in the research. The problem with this claim is that you’re always burning fat at rest, and, depending on your intensity, during exercise, too. Insulin’s effect on fat burning only occurs after a meal. A number of factors more directly affect your body-fat composition than insulin. This includes energy balance (how many calories you eat versus how much exercise you get), strength training, hormonal factors and genetics.
2. Low-carbohydrate foods help control cravings.
This claim definitely has some meat to it. It’s something I say to my clients all the time: The more sugar you eat, the more sugar you want. Cutting back on sugary sweets and refined carbohydrates can help decrease your cravings for them over time. But, an even more effective (and easier!) strategy is to eat more protein. Studies show that protein helps you feel full for longer periods of time, which can reduce food intake overall and even reduce cravings. In fact, one study showed that eating a high-protein breakfast (40% protein) caused a decrease in food cravings and late-night snacking. This appetite-controlling effect is seen without purposely limiting calories, allowing you to feel full on less food.
3. It takes more energy (aka calories) to digest protein.
This claim is also true. Similar to its satiating effects, protein also increases your energy expenditure. It does this by something called the thermic effect of food. All foods require energy to digest, and protein uses up the most. It takes about 20–35% of the calories in protein-rich foods just to digest it. Depending on your protein intake, this can amount to a significant calorie savings each day. The potential danger of eating too much protein is that it can be taxing on your kidneys.
So what’s really behind the weight loss seen on a low-carb diet? It’s likely a combination of factors, including the ones mentioned above. Additionally, when someone undergoes a lower-carb eating plan they may choose more quality carbohydrates (e.g., fruit, veggies, whole-grains) in lieu of refined carbohydrates (e.g., white bread, sweets, pasta).
Recommendations for Eating Low-Carb
If your weight struggle centers around cravings for too many sugary snacks and other refined carbohydrates, a low-carb, high-protein diet may be effective for you. Increasing protein while limiting refined carbohydrates and sweets can help increase satiety and thwart cravings. If you do choose to follow a lower-carb eating plan for weight loss, here are three things to consider:
1. Focus on food quality.
Before getting started, take a good look at your overall diet quality and find areas where you can make an upgrade. Switch to nutritious protein sources like lean cuts of meats and poultry; fish and seafood; low-fat dairy and eggs. Seek out rich sources of omega-3 fats like salmon, sardines, flaxseed and walnuts. Enjoy plant-based fats like avocado, nuts, seeds and olive oil. Limit your intake of fried and highly processed foods. Increase your vegetable intake, and make sure to get some leafy greens every day. And don’t forget about fermented foods! One or two servings per day of low-sugar yogurt, tempeh, sauerkraut or kimchi can help balance your gut bacteria.
2. Watch your portion sizes.
For improved portion control, try practicing the plate method. Strive to make half your plate leafy greens and vegetables. Then balance the remaining half with lean protein, healthy fats and high-fiber carbohydrates like beans, quinoa or berries.
3. Choose higher-quality carbohydrates.
It’s not necessary to completely avoid carbohydrates while on a lower-carb diet. Start by reducing or eliminating highly refined carbohydrates (e.g., white flour, white bread, snack foods) and sugar (e.g., soda, candy, sugary cereals). Then, begin increasing high-fiber foods like leafy greens, vegetables, low-sugar fruits, whole grains and beans. Getting enough fiber is super-important for weight loss while on a low-carb diet. It’s not only essential for optimal digestive tract health (yup, it keeps you “regular”), but it also helps slow the release of carbohydrates into your bloodstream. This effect helps to stabilize blood sugar levels and keep your appetite (and those sugar cravings!) under control.