Taking diet pills, exercising around the clock, engaging in restrictive eating habits and following trendy diets promising to speed up metabolism are just a few of the methods people use to drop weight fast. While a tempting concept, most experts maintain that rapid weight loss is neither healthy nor sustainable, and even somewhat deceiving. There is a long and short answer to the question, “How much weight can you lose in a week?” Sure, if you stop eating altogether and amp up exercise, you can lose up to 30 pounds in a week. How much weight should you aim to lose in a week? The majority of experts—including the Centers for Disease Control and Prevention—unanimously agree that an average of one to two pounds of weight per week is a healthy weight loss goal. In fact most of them, including Jenna Kilgore, MS, NASM CPT, FNS and Noom Coach, maintain that suddenly losing a lot of weight is less sustainable than slow and steady weight loss. What happens when you lose weight too fast? Overall rapid weight loss may include side effects such as headaches, dizziness, fatigue, constipation, hair loss, muscle loss and even gallstones, notes Keri Gans, RDN, a nutrition consultant and the author of The Small Change Diet. Dr. Wajahat Mehal, MD, PhD, weight loss expert with Yale Medicine and director of the Weight Loss Program and professor at Yale School of Medicine, suggests looking at the big picture, focusing on how much weight you can lose overall versus how much weight you can lose in a week. “Total weight loss with lifestyle intervention is generally 3-4% of starting weight,” he explains. There are a number of factors that contribute to weight loss, which may result in a more rapid or gradual weight loss. “Weight loss is a complicated process, kind of like putting a puzzle together,” adds Kilgore. In other words, you may be able to lose more or less than the average one to two pounds per week due to these variables. Here’s everything you need to know about how to do it safely—because yes, that really is the most important thing.
7 variables that contribute to weight loss
1. Body mass
Kilgore explains that someone who is starting off at a higher BMI is more likely to lose more weight in a week than someone with a lower one. Additionally, while science has concluded that muscle doesn’t actually weigh more than fat (a pound of muscle weighs the same as a pound of fat) it is denser. This is why most health and fitness experts rely more on body composition measurements than simply the weight on the scale.
2. Water weight
“Water weight is more of a sign of quick weight loss than sustained weight loss,” explains Gans. “Since our body is made up of 60% water it is not uncommon to see weight fluctuations from one to five pounds in a given day.” Bottom line: You shouldn’t consider water weight loss true weight loss, because it will come back as soon as you hydrate.
3. Calorie deficit
When attempting to lose weight, most people focus on calorie intake. While seriously restricting caloric intake will inevitably lead to rapid weight loss, experts suggest taking a more moderate and sustainable approach with your total number of calories consumed per day dependent on how many you burn. For example, a more active person who is regularly exercising needs more calories than someone who is sedentary. However, overall “a 500 calorie deficit per day should lead to one pound per week of weight loss,” maintains Gans. A doctor or weight loss expert can help you determine a healthy deficit goal using bioimpedance analysis, or BIA, which uses factors such as your muscle mass and basal metabolic weight to figure out what your caloric deficit should be.
4. Nutrition
When it comes to sustainable weight loss and food, calories aren’t the only thing that matters. “Nutrition is the most important aspect of a healthy weight,” stresses Dr. Mehal. “Without changing the home food environment it is very difficult to have significant weight loss.” In the Dietary Guidelines for Americans 2020–2025, the USDA explains that a healthy eating plan is not only one that stays within your daily calorie need but involves fruits, vegetables, whole grains, and fat-free or low-fat milk and milk products, protein-rich food including seafood, lean meats and poultry, eggs, legumes (beans and peas), soy products, nuts, and seeds, and is low in saturated fats, trans fats, cholesterol, salt (sodium), and added sugars.
5. Movement
Movement is essential in any wellness journey. “Finding ways to move throughout the day, whether that be short bursts or longer, more intentional workouts, or both, can have a lot of benefits,” says Kilgore. “Exercise is very beneficial for health even without weight loss,” reminds Dr. Mehal. Not only does it help burn calories, but promotes mental and physical health, releasing feel-good hormones. “It can cause a boost of endorphins that can also domino into our other choices too,” Kilgore adds.
6. Sleep
Sleep has a big impact on our overall health, Kilgore maintains. In fact, multiple studies, including one from July 2011 published in Current Opinion in Clinical Nutrition and Metabolic Care, link decreased quality and quantity of sleep to obesity. “When we don’t get enough sleep, we may find ourselves hungrier and more often craving our comfort foods,” she explains. “We also tend to have lower energy, which can impact our daily movement, our motivation, etc. A good night’s rest is paramount, especially when working on a weight loss goal."
7. Stress
While stress is normal, too much stress can wreak havoc, specifically on our hormones. “A prolonged increase in cortisol is linked to abdominal fat storage,” Kilgore explains. Not only can stress affect our hunger and fullness cues which can lead to overeating, it can also result in reaching for those comfort foods and ignoring portion sizes. “Chronic stress often shows up as a plateau in progress,” she says.
Expert endorsed tips to encourage healthy weight loss
In order to maximize weight loss in the healthiest and most sustainable way possible, follow these expert-endorsed weight loss tips.
Fill up on fiber
Fibrous foods are your friend when it comes to sustainable weight loss, says Gans. “Fiber-rich carbs, such as 100% whole grains, fruits and veggies, take longer to digest in the body than refined carbs causing more satiety at mealtimes,” she says.
Don’t eliminate foods you love
Instead of ditching your favorite foods, Gans suggests modifying them. “For example, don’t stop eating pasta, and instead try to make it healthier.” Swap your go-to huge bowl of fettuccine Alfredo, for a healthier dish with one-cup cooked pasta tossed with sautéed spinach and grilled shrimp. Or, instead of eating a whole pizza topped with sausage and pepperoni, limit yourself to two slices with spinach and mushrooms, supplementing it with a large mixed green salad on the side. “Want French fries with the burger? Go for it, but perhaps lose the bun,” she advises.
Focus on progress, not perfection
“Trying to eat healthy 100% of the time is unrealistic and unwarranted,” says Gans. Instead, focus on a more realistic and smarter approach, such as making healthy choices 85% of the time, and allowing yourself to indulge in whatever you wish the remaining 15%. Dr. Mehal agrees that mindset is key. “Most people have too high expectations and then feel as though they have failed,” he states.
Try the plate method
Gans also suggests creating most of your meals with the plate method in mind, filling your dish up with one-half veggies, one-quarter carbohydrate, and the remaining one-quarter protein and a fat serving. “By default, your portions will be more in check and the protein and fat will help fill you up,” she says.
Stay hydrated
The more water you drink, the less you will eat, maintains Gans. “Many times individuals confuse thirst for hunger. Simply try and stay hydrated by drinking more water and/or unsweetened, low-calorie beverages,” she suggests.
Focus on the “whys” of weight loss
Kilgore stresses the importance of staying connected to the “whys” instead of the “hows.” “Remembering why losing weight or reaching our goals is important can go a long way,” she says. “Motivation can be fleeting and that is one of the biggest challenges we see. When a motivational low hits, it can be hard to power forward. Learning to navigate those ebbs and flows will be valuable in the long run.”
Find a support system
It’s so important to have a strong support system to reach your weight loss goals. “The process can feel lonely at times,” Kilgore explains. She suggests building up a support system of family members, friends, coaches, and anyone who can help provide motivation and accountability.
Bottom line: Weight loss is an individualized journey
Remember that there is not a one-size-fits-all approach to weight loss and how much weight you can lose in a week. “Everyone’s journey to weight loss is their own,” notes Kilgore, who recommends keeping the focus on sustainability over speed. “Consistency is a huge factor since this journey can take time and patience to put all of the puzzle pieces together, which can be really mentally trying. Of course, weight loss is not a linear process so pauses, ups, and downs are totally normal along the way! It’s important to look for an overall downward trend.” Next up, read about a delicious and filling 7-day meal plan that will supercharge your weight loss efforts
Sources
Jenna Kilgore, MS, NASM CPT, FNS, Noom CoachKeri Gans, RDN, a nutrition consultantWajahat Mehal, MD, PhD, weight loss expert with Yale Medicine and director of the Weight Loss Program and professor at Yale School of MedicineUSDA:Dietary Guidelines for Americans 2020–2025CDC: Losing WeightCurrent Opinion in Clinical Nutrition and Metabolic Care: Sleep and Obesity
