Wellness

How Your Body Fights Weight Loss

How Your Body Fights Weight Loss

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And Why It Wants to Gain Weight Back

Weight management is a key component of a healthy life. While many people successfully maintain healthy weights through a balance of nutrition and activity, weight loss can be vital for the 71 percent of Americans who are overweight or suffering from obesity. However, weight loss – particularly extreme weight loss – is more complicated than consuming fewer calories than you burn. As many as 90 percent of people who have lost a considerable amount of weight will gain it back.

Sustainable weight management is possible and understanding how your body responds to weight loss efforts can help you establish realistic expectations on your journey.

Here are 8 things you may not know about your body and weight loss.

1. Your Metabolism Will Slow Down to Store Fat

The more you work out or manage your calorie intake to lose weight, the more your metabolism wants to compensate by slowing down to maintain your current weight. Metabolic compensation kicks in to preserve and store fat for future energy. Some physicians theorize this is because the human body has evolved to value storing fat and energy and to interpret a shortage of calories as sign of distress or famine.

2. Your Hormones Will Increase Drive to Eat

Unfortunately, metabolic compensation isn’t your body’s only strategy to prevent weight loss or encourage weight gain. Hunger hormones – leptin and ghrelin – are also at play. Fat cells produce leptin, which tells your brain when you’re full. Fat cells also shrink when you lose weight, producing less leptin and meaning you don’t feel as full. Strike one. Ghrelin, produced by the stomach, tells the brain it’s time to refuel. When you lose weight, ghrelin levels rise, prompting you to want to eat more frequently. Strike two. Research suggests that neither leptin levels nor ghrelin levels return to a normal baseline for at least a year.

3. Your Brain Won’t Register How Much You’re Eating

In addition to your metabolism and hormones, the neural circuitry in your brain is fighting weight loss too. Food has a greater reward value after you’ve lost weight and the part of the brain that regulates food restraint becomes less active – meaning that while you’re eating more to feel full (courtesy of leptin), you’re also less aware of how much you’re eating.

4. Your Genes May or May Not Be Helping

More than 400 genes have been linked to obesity and weight gain and they can affect appetite, metabolism, cravings and body-fat distribution. The exact degree to which you can be genetically predisposed to weight gain or obesity is unclear, but genes have been associated with difficulty losing weight even as you increase physical activity or low-calorie diets. Much like weight management on the whole, addressing a genetic predisposition for obesity is much easier from a preventative standpoint than a reactionary one.

5. Your Body is Extra Prepared for Your Second Try

When your body gets sick, it creates antibodies to the illness so that the next time, the immune system is prepared. Unfortunately, it reacts in a similar way to weight loss. If you’ve lost weight in the past due to exercise or diet changes and attempt those same strategies again to lose weight, your body – again, mainly hormones and metabolism – will adjust to prevent similar damage and you’ll see fewer weight loss results.

6. Your Weight Has a Favorite Number

Some scientists subscribe to the idea that your body has a set weight point and all of the above – your metabolism, hormones, brain – will adjust to maintain that weight. The theory goes that people can have naturally higher or lower set weights than others and genetics, aging, history of weight loss and other hormonal shifts can all impact your set weight. Moreover, set points can rise but very rarely do they lower. Similarly, they are much easier to maintain – because your body wants to – than reduce, which is why maintaining a healthy weight is easier than losing weight.

7. Your Weight Loss Might Not Look Like You Were Expecting

Unfortunately, it’s not always smooth sailing after successful weight loss – especially successful extreme weight loss – either. Your body may look different than you were expecting. Stretch marks and loose skin are common, and many people deal with the emotional affects of coping with a body that does not look like the ideal they had in mind.

8. Your Emotional Health Remains Independent of Your Weight

A result of this is the tendency for people to tie happiness and emotional health to weight loss and, when they have successfully lost the weight but remain dissatisfied with other aspects of their life, fall into a cycle of dissatisfaction. Guilt at not feeling happy after weight loss can also factor in, as can the temptation to eat to cope with these feelings. Moreover, some people can experience an uncertainty about what’s next after losing significant amounts of weight if that’s been their primary goal.

What Can Help

Some simple strategies, such as making protein a staple of meals and snacks or starting a weight loss routine with cardio before switching to weight training and resistance later on, can help support your weight loss goals. Many people find it beneficial to focus on small, achievable lifestyle goals to work on their emotional health alongside weight loss. For example, rather than looking for a low number on the scale, you may focus on reaching a point where you feel comfortable playing sports or attending a group fitness class. Similarly, aiming for moderate goals that can gradually build to bigger change can help you avoid the pitfalls of rapid, short-term solutions.

“Both medical and surgical assisted weight loss programs have proven to be very successful, but the key element is you,” says Matthew R. Pittman, MD, director of bariatric surgery, Northwestern Medicine Regional Medical Group. “Committing fully to the behavioral and lifestyle changes required is essential for long-term weight loss success.”

Working with a lifestyle medicine professional can also help you manage expectations, set reasonable goals and respond to your body’s changes if weight loss is a goal of yours. You may also want to consider whether a nutritionist is right for you. The team at the Northwestern Medicine Center for Lifestyle Medicine specializes in setting achievable goals ranging from comprehensive weight-loss treatment and management for overweight and obese adults and educational strategies that promote weight loss to risk factor reduction and tools to improve physical activity and encourage healthy eating.

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