Why Do I Gain Weight So Easily? 7 Reasons for Unwanted Weight Gain

why do I keep gaining weight
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Weight loss is not easy for most people. And it can be downright frustrating if your attempts at trying to lose weight seem to go in the opposite direction. Instead of watching the numbers on the scale go down, they seem to continuously creep up. You may wonder to yourself, “Why do I gain weight so easily?”

If these frustrations resonate with you, there may be a number of reasons why you struggle with your weight. The good news is, many of these reasons have simple explanations that are easy to fix.  Here are some of the most common reasons for unwanted weight gain and what you can do to address them.

Common Reasons for Unwanted Weight Gain

Many factors influence your weight, including diet, exercise, lifestyle, and genetics. Though you cannot control all the factors that contribute to your unwanted weight gain, there are many that you can. Here are some common reasons for unwanted weight gain.

Unrealistic Goals

Like many people, when you start a weight-loss program you want to lose a lot of weight as quickly as possible. You may follow restrictive eating plans or intense workout programs that are hard to manage long-term. Your desire to lose as much weight as possible in as short of a time as possible may be why you are gaining weight instead of losing.

According to a 2018 study published in Preventive Medicine Reports, setting unrealistic goals leads to poor weight-loss outcomes and feelings of helplessness when it comes to the idea of losing weight in the future. Your unrealistic weight-loss goals may also make it harder for you to maintain your weight loss.

Portion Sizes

Your portion sizes may explain why you are gaining weight instead of losing. Portion sizes have been increasing at restaurants and at home for years, according to a 2018 review published in The Proceedings of the Nutrition Society. What you consider a normal portion of food, may be significantly larger than the standard portion size.

The authors of the 2018 review note that not only are portions larger than they used to be, but people are eating large amounts of high-calorie, low-nutrient foods. Consuming large portions of high-energy, low-nutrient foods increases overall calorie intake, leading to weight gain.

However, eating larger portions of any type of food, including nutrient-dense foods like fruits and whole grains, can increase calorie intake and lead to weight gain as well. Portion sizes count whether you are eating high-calorie foods or nutrient-dense foods. 

Food Choices

Even if you are careful about calories, your food choices may be why you are gaining instead of losing. A 2019 study published in the scientific journal Cell Metabolism investigated the effects of consuming an ultra-processed food diet on eating habits and weight in a small group of adults.

The participants ate a minimally processed diet for 2 weeks and an ultra-processed diet for 2 weeks. The researchers found that when given a diet filled with ultra-processed foods—foods high in fat, salt, and sugar—the participants ate 500 more calories a day, ate faster than they did following the minimally processed foods, and gained two pounds.

The study in Cell Metabolism only included 20 participants and more studies are needed to better understand the effects ultra-processed foods have on appetite and weight. However, a systematic review and meta-analysis of 43 observational studies published in Obesity Review also found a strong correlation between ultra-processed foods and weight struggles.

Lack of Movement

Modern life has made many things more convenient. You can change the channel without leaving the couch and even order groceries online that get delivered right to your door. But these modern conveniences also make you less active. 

Most adults in the U.S. engage in very little physical activity—or no physical activity at all—according to the Centers for Disease Control and Prevention. When it comes to weight management, exercise is part of the equation, and every bit of movement counts. If you are working from home and ordering everything you need online, your unexpected weight gain may be due to your change in lifestyle. 

Increased Exercise

Are you working out more? Then your increased exercise may explain your weight gain. Whether doing aerobic activity or strength training, your exercise routine may increase muscle mass, which may cause the number on the scale to go up. Instead of obsessing over the number on the scale, use your clothes to monitor body changes. 

Working out strengthens and builds muscle. Forcing your body to work out harder creates tiny tears in your muscle, which ultimately leads to muscle gains. This also causes inflammation, fluid retention, and weight gain.

Exercise is good, but it also boosts your appetite. Your unexpected weight gain may be because you are eating more. Be mindful of your food choices and portions to keep calories and appetite in check. 

Medications and Health Conditions

Numerous medications and health conditions also cause unwanted weight gain. Hormonal birth control, corticosteroids, and medications used to treat mental health conditions make people more prone to weight gain.

Hormone-related health conditions like hypothyroidism, polycystic ovarian syndrome (PCOS), and Cushing syndrome, also cause weight gain. Additionally, women experience weight gain during their menstrual cycle because of fluid retention.

Sleep and Stress

Lack of sleep and too much stress are also common causes of unwanted weight gain. When you do not get an adequate amount of sleep, your body turns excess calories into fat, your appetite increases, and you eat more.

Short-term stress is normal. It improves focus and boosts energy to help you get through the stressful situation. But chronic stress is bad for your health and your weight. When you always feel stressed, the stress hormone cortisol remains high. Cortisol is an anabolic hormone that reduces muscle mass and increases fat accumulation.

Strategies to Reverse Unwanted Weight Gain

When you want to develop strategies to reverse unwanted weight gain, you first need to find out what is behind the extra weight. Schedule a consultation with a healthcare provider for some guidance. They may run lab work to check for health conditions that might contribute to your weight problems or review your medications.

Once you know the cause of your weight gain, you can develop strategies to tackle the cause. You also can talk to a registered dietitian for guidance. These health professionals can help you create a nutritious and balanced meal plan, teach you how to keep portions in check, provide suggestions on how to incorporate movement into your daily routine, and make exercise recommendations.

They may also offer strategies to help you manage stress, such as exercise or meditation. Additionally, consider adding regular exercise and stress management techniques to your routine. These will boost your weight management efforts and may even improve your sleep helping you to get the recommended 7 to 9 hours of sleep a night.

When it comes to weight and weight loss, no single strategy works for all. Working with a healthcare professional who specializes in weight management, like a registered dietitian, can help you better understand the causes of your weight gain so you can make the appropriate adjustments that help you reach your goals. 

A Word from Verywell

Although you cannot control all the factors that cause unintentional weight gain, you can make changes to your lifestyle that make it easier for you to manage your weight—like eating a balanced diet, getting regular exercise, finding healthy outlets for stress, and sleeping 7 to 9 hours a night.

But, more importantly, try not to focus on that number on the scale. Instead, pay attention to how you feel physically and mentally. Making positive changes to your lifestyle boosts your energy and gives you a better sense of well-being. If you find that despite your best efforts you still continue to gain weight, it may help to speak with a healthcare professional or registered dietitian for advice.

Frequently Asked Questions

  • How do I create realistic weight loss goals?

    You can create realistic weight-loss goals working with a health professional. Talk to a primary care provider or a registered dietitian for guidance. They can help you make short-term goals to keep you motivated so you can achieve your long-term goals.

  • What is energy balance?

    Energy balance means the number of calories you eat equals the number of calories you burn. Maintaining energy balance helps you manage your weight.

  • How can I monitor my weight without a scale?

    There are many ways to monitor your weight without a scale. How your clothes fit is one way. You can also use before and after pictures. Or, you can get your body composition measured by a healthcare professional.

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Verywell Fit uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read our editorial process to learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.
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