Health / Weight Loss

How Much Fat Can You Actually Burn in One Week?

Drop the unrealistic expectations—here's a healthy number to aim for.

The internet is filled with success stories of rapid weight loss that happens in only a few weeks—and sometimes even in just one!

But is that really possible? We talk to two experts, who tell us whether it’s safe to lose a significant amount of weight in a short period of time and the healthy ways to do so.

How much weight can someone realistically lose in, let’s say, a week?

Claire Shorenstein, M.S., R.D., C.D.N., explains, “Typically, a healthy weight-loss rate falls between 0.5 and 2 pounds per week. Even though the goal is to lose weight, it’s still crucial to be consuming enough calories/nutrients to meet your individual nutrient needs.”

Along with a proper diet, Aaptiv’s cardio and strength training workouts can have you losing weight before you know it.

Registered dietitian Lauren Antonucci, a board-certified specialist in sports nutrition and the founder and director of Nutrition Energy, adds, “Possibly counterintuitively, [even] those with the highest activity level generally cannot lose more than 0.5 to 1 pounds per week since their high level of activity and calorie burn leaves them both hungry and with high recovery needs.”

Shorenstein makes another great point: “Something to keep in mind with regards to weight loss… just because the scale doesn’t shift doesn’t mean that you haven’t made progress.” While many people place so much focus on the scale, it should be used as a guide rather than the one and only way to measure your progress. Other ways of tracking your weight loss include noticing how your clothes fit and improvement in sleep, energy level, or exercise performance.

So, when people claim to lose ten pounds in one week—is it fake news?

These scenarios are not completely false, but they’re not all true either. Shorenstein and Antonucci agree that when someone claims to have lost a significant amount of weight in a short period of time, it isn’t just fat they’re losing, even if the scale number decreases.

“Any weight lost in this extreme manner is not fat loss, as is generally what is desired, but water weight and fluid shifts due to lower carb intake,” Antonucci says. She explains that “carbs are stored in the body with three times as much water. It can cause extreme fluid and electrolyte shifts.” Going on a low-carb diet will result mostly in fast water weight loss as opposed to fat loss.

Shorenstein adds, “It is not safe to lose a large amount of weight rapidly, especially over a prolonged period of time, [because] you increase your risk of becoming malnourished as you are likely not meeting your nutrition needs.” So, the next time you see an advertisement showcasing a dramatic weight transformation that seems too good to be true, it probably is. In these cases, it’s likely due to water weight loss and fluctuation.

Slow and steady wins the race.

As you’ve probably guessed, we’re preaching the slow-and-steady method. Don’t dramatically change all your habits at once and hope for a huge transformation. Instead, aim for sustainability, regardless of your weight-loss goal. You want to be able to maintain this lifestyle change without having to resort to extreme measures. “Quick fixes and crash diets are never good long-term solutions,” Antonucci says. “We need to make lasting habits and lifestyle changes. That doesn’t sound as sexy…but it actually works!”

Shorenstein recommends focusing on healthy behavioral changes that you can realistically sustain. This also means you can avoid potential muscle loss, which can happen with faster weight-loss rates.

What are some ways to become healthier without resorting to quick fixes or crash diets?

Make better food choices.

The first step is making better food choices. It’s important that your meals are balanced with enough protein and healthy fats. Make sure you get five servings of vegetables every day—Antonucci notes that “this is a must.” Shorenstein suggests non-starchy veggies as well as “a portion-controlled amount of fiber-rich carbs. [This includes] fruit, whole grains, starchy veggies, and beans or legumes.”

Eat when you’re hungry.

Shorenstein adds, “Don’t let yourself go to extremes of hunger and fullness. Check in with yourself before you eat to see if you’re really hungry when you feel the urge to mindlessly eat.” We’ve all been there, when we’re so hungry that we eat anything and everything in sight, so don’t try to go without eating for long. In these situations, we tend to lose control around food. Eat when you’re hungry, and stop when you’re not. Listen to your body cues.

Make your treats worth it.

Don’t deprive yourself. Nothing will set you up for failure more than telling yourself you’ll never eat another chocolate bar or cookie again. What’s life without treating yourself once in a while? But as Shorenstein says, “Choose to eat your treats intentionally. Make it worth it, and savor every bite without guilt. Don’t deprive yourself, but don’t eat something just because it’s there.”

Drink water.

It goes without saying, but we have to say it—drink water! Antonucci advises consuming “at least half your body weight in fluid ounces per day.”

Stay active.

“Start moving more,” Antonucci adds. “Any gradual increase in activity will not only be good for your health, but [it’ll also] leave you feeling good about yourself.” Another upside to making the decision to be more active is that it’ll generally lead to better food choices. Your body will thank you for it.

Small changes can lead to big changes.

Too often, people want to completely overhaul their lifestyle. But too many simultaneous changes from your usual habits and routine can be too much to handle at first.

“You don’t need to go on a ‘diet’ to lose weight. You just need to figure out what the best eating style and approach is for you and your specific lifestyle,” Shorenstein says. “Often what I work on with clients involves many small nutrition upgrades, which add up to big change over time.”

This circles back to the slow-and-steady method. Don’t be too hard on yourself and expect big results immediately.

Little choices you make each day can cause significant results especially if you’re doing your Aaptiv workouts consistently. As long as you’re consistent and stick to them, you’ll be surprised by how far you’ve come when you look back.

Health Weight Loss


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