Some people claim that alternating between “high carb” and “low carb” days will help you drop pounds. But is it legit?
Nutrition trends come and go in waves. First, we were scared of eating too much fat. Then the conversation started to shift, and we started demonising carbs.
In a way, our fear of carbs makes sense. Carbohydrates make up a large portion of your daily calories, and eating too much of the not-so-great kind, like sugary drinks, white bread, and cookies, can be problematic if you’re looking to lose weight or just get healthier.
So you might choose to cut out carbs altogether, but that type of restriction isn’t entirely necessary. Eating the right kind of carbs, like oats and brown rice, provides your body with the fuel you need to not only get through your workouts, but also your day in general. That’s why some people opt for a strategy called carb cycling, meaning they alternate between high carb days and low carb days.
“Carb cycling is a way to help dieters periodically feel like they’re not dieting and in some cases actually indulging,“ says Men’s Health nutrition advisor Alan Aragon, M.S.. This doesn’t mean you’ll get a special fat-burning effect by going low carb, but it might help you stick with your diet in the long run, he adds.
But does this approach do anything for your weight for the long haul? Even more importantly, is it any better than simply cutting calories overall? Here’s your beginner’s guide to carb cycling and how to figure out if it’s a fit for you.
What Is Carb Cycling?
Carb cycling means you eat a higher amount of carbs one day, followed by a lower amount of carbs the next. You continue to alternate between the two throughout your week, depending on your activity levels on each day.
The rationale behind it is pretty solid: you get the perks of going high-carb during the days you work out, and the perks of going low-carb when you’re not as active.
When you exercise, your body dips into your carb stores for energy, so naturally your high carb days would align with training days, when your body can best utilise that fuel. That can be a great thing, because an extra push during your workout means you can go harder for longer, burning more calories overall. On your rest days, you can scale your carbs back as a way to reduce empty calories without feeling too restricted for the rest of the week.
So let’s say you’re 175 pounds and aiming for 2 grams of carbs (g) per pound of body weight on your high-carb days. If you’re training on a Monday, that’s 350 g. On your following rest day, or low carb day, you might cut back to just 1 or 1.5 grams per pound of body weight, ranging anywhere from 175 to 263 g.
That said, there’s no set amount for how many carbs you’re allowed on higher or lower carb days. It depends largely on the types of workouts you’re doing, and how often you do them. As with most diets, there are a variety of carb cycling “prescriptions” available on the internet, but your carb intake should ultimately be tailored to you and your needs.
4 Things You Should Know Before You Try Carb Cycling
Carb cycling requires a bit more planning than most people prefer, because you need to weigh, measure, and count grams. Using an app like My Fitness Pal can help make that easier, but if you appreciate flexibility in your diet, carb cycling might be too strict for you.
That said, if you love having guidelines or “rules” to follow, carb cycling can be worth a shot for you.
Here are a few things to keep in mind before you give it a whirl.
1. KNOW HOW MANY CALORIES YOU NEED
Establish a daily calorie goal you’ll aim for on all days. A general approach: If you want to lose weight, multiply your bodyweight times 10. That’s how many calories you’re aiming for each day. Weight maintenance? Multiply by 12. And if you want to gain, multiply by 15.
2. BALANCE OUT YOUR MACROS
Divide those calories among your main macronutrients: carbs, protein, and fat. Carbs and protein both provide 4 calories per gram, while fat provide 9 calories per gram.
In addition to your carb cycling, aim for about 1 g of protein per pound of body weight. Make up the rest with healthy fats. (For a more detailed plan, here’s how to count your macros for weight loss.)
So on high carb days, you’ll up the carbs and your calories, keeping protein and fat the same. On the flip side, the lower carb days will slash your calories, again while keeping your protein and fat the same. Remember, it’s about eating less calories but not really “feeling” like you are.
3. DON’T NIX THE FIBRE
When you eat fewer carbohydrates, make sure you keep the fibre. Low carb days aren’t an excuse to dump the broccoli and apples. Focus primarily on removing added sugar and other refined carbs, like muffins and bagels, from your diet. Load up on fibre and nutrient-rich vegetables, fruit, beans, oats, quinoa, and other quality grains.
4. EAT ENOUGH, EVEN ON LOW CARB DAYS
Your brain runs on carbs, or more specifically, the sugar glucose. And when there’s none around, your body has to make it using other sources, like protein, which can be bad news if you’re looking to build and maintain lean muscle. That’s why it’s so important to eat more than 130 g of carbs on your “low carb” days. Feed your brain so you’re not in a fog the entire day at work.
Chris Mohr Ph.D, R.D., is the owner of Mohr Results. He has Bachelor and Master of Science degrees in nutrition from The Pennsylvania State University and University of Massachusetts, respectively. He earned his Ph.D. in exercise physiology from the University of Pittsburgh and was formerly the consulting sports nutritionist for the Cincinnati Bengals and University of Massachusetts Athletic Program.