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10 Unexpected Causes of Weight Gain

Weight Gain Causes

One of the most frustrating health issues facing the people of the 21st century is weight management. Most of the world’s population live in countries where problems with obesity are more prevalent than starvation. In fact, obesity is the fifth leading health risk in the world.

When people unexpectedly gain weight, they often turn to the obvious culprits including genetics, diet, and exercise. However, not all causes of weight gain are so easy to identify. For example, what causes weight gain when the person’s diet and exercise routine haven’t changed? Is our diet solely responsible for the ten pounds we gain suddenly, or are there other factors involved?

Causes of Weight Gain

Sudden weight gain can seem mysterious, especially when it happens suddenly. One day, we step on the scale and realize that there is a reason our pants have been so tight lately. Keep reading to learn some of the surprising reasons that could be behind your extra pounds.

1. Hypothyroidism

The thyroid is a butterfly-shaped gland located in your neck. Hypothyroidism is an autoimmune response that slows down your metabolism. Your metabolism is your body’s system for converting food and drink into energy. A slow metabolism means that the body burns less fat for energy and does not efficiently burn calories while at rest. One of the most common symptoms of hypothyroidism is sudden weight gain.

Other symptoms of hypothyroidism are:

  • Low energy levels
  • Intolerance to cold
  • Dry skin
  • Hair loss
  • Puffy face
  • Muscle weakness

The weight gained by people with hypothyroidism isn’t all fat. Instead, an accumulation of water and salt can make you gain anywhere from five to ten pounds. The lack of energy can also lead you to exercise less which can also lead to weight gain.

2. Seasonal Affective Disorder

If you gain weight with the seasons, your added pounds could be related to Seasonal Affective Disorder. SAD is a mood disorder associated with the lack of sunlight in the fall and winter months. It affects a person’s circadian rhythm which controls sleep patterns and mood regulation.

In the fall and winter, some people’s brains can react to the change by slowing down serotonin production. Serotonin is the feel-good neurotransmitter that keeps us from feeling depressed.

Weight gain is a common symptom of SAD as are depression, anxiety, and low energy levels. The easiest way to deal with SAD is to invest in a SAD light, a device that simulates sunlight and boosts serotonin production. You use the SAD light in the morning to help your brain wake up in the absence of regular sunlight.

3. Medication

Modern medicine does its best, but our bodies exist in a delicate balance that science has yet to fully understand. A few of the common medications that often have weight gain as a side effect are birth control, antidepressants, and steroids.

  • Birth control is a well-known cause of weight gain. Usually, the added weight appears in the weeks following the introduction of a new birth control pill. Changes in estrogen levels trigger the body to hold onto water which accounts for small fluctuations in weight around a woman’s cycle.
  • Antidepressants are another possible culprit for unexpected weight gain. Experts estimate that a quarter of people on antidepressants will gain 10 pounds or more. Usually, when you gain weight because of antidepressants it is because you are taking the medication long-term. While the exact cause is unknown, most doctors attribute weight gain to the medication’s effect on appetite and metabolism.
  • Steroids are used by about 5% of the American population to gain muscle mass. However, this popular exercise-related medication changes the body’s electrolyte and water balances which can cause fluctuations in weight. It also negatively affects our metabolism and stress response.

If you’ve recently started taking a medication such as birth control, antidepressants, or steroids, check with your doctor to see if they could be a potential cause of your weight gain.

4. Hormonal Weight Gain

Most people understand that hormones influence us, but they may not understand the full extent of their power in the body. Our metabolism relies on thyroid hormones T3 and T4, our sex drive on the sexual hormones estrogen, progesterone, and testosterone, our appetite on the hunger hormones ghrelin and leptin… the list goes on and on.

A few symptoms that may indicate hormonal weight gain include:

  • Thyroid goiters
  • Fatigue
  • Sudden weight gain in stomach
  • Impotence or amenorrhea
  • Excessive hair growth (especially in women)
  • Hair loss
  • Changes to appetite including cravings for fat, salt, and sugar

The primary body systems responsible for hormone production are the brain and the endocrine system. Together, these systems reach across the body, triggering the release of certain hormones in response to a variety of situations. If one is unbalanced, the other systems may have to work harder to compensate.

Hormonal weight gain is especially difficult to diagnose, especially without your doctor’s help. Certain tests can tell you which of your hormonal systems are being affected. Speak to your doctor if you think your problems might be related to a hormonal imbalance.

5. Alcohol

Alcohol’s effect on weight is a topic that has been under scrutiny lately. Red wine, in particular, has been praised for its health benefits. A glass of red wine contains certain polyphenols that change stubborn white fat into brown fat that burns more easily, but only if you drink one glass a night.

While drinking certain types of alcohol in moderation can help with weight loss, overindulging can put a huge dent in your weight loss plans.

Moderation for women is about 1-2 servings a day and for men about 2-3 servings per day. When we drink more than the recommended amount, alcohol changes the way the body burns fat. Your body focuses on getting rid of the alcohol instead of burning calories from food. It lowers testosterone levels which could affect weight loss and stop the formation of lean muscle. Alcohol also interferes with impulse control, leading to overeating and poor food choices.

You do not need to completely cut alcohol from your diet to experience significant weight loss. Instead, try regulating how much you drink on a daily basis with smaller goals like only drinking one glass with dinner or not drinking on weekdays.

And remember, drinking in moderation does not mean saving all of the drinks you didn’t have during the week for the weekend!

6. Depression

At first, the link between weight gain and depression might seem pretty straightforward. How many of us reach for sweets when we are upset? For many people, food can be comforting especially when we are at our lowest. Then there is the fact that people who are depressed are more likely to be obese and people who are obese are more likely to be depressed.

But, of course, the relationship between weight gain and depression is a bit more complicated than it first appears. When we are depressed, the brain’s reward system is not functioning properly. Activities, experiences, even our favorite foods, no longer give you the same pleasure as they used to. In response, you may start to have uncontrollable cravings for food to elicit some reaction from your body.

Depression also affects impulse control which affects our ability to say no. No to junk food, no to the urge to sit on the couch all day, no to the decision to stay out all night prior to a big day at work. Between the lack of pleasure and lack of control, weight gain in people with depression is not so surprising.

7. Food Sensitivities

Food sensitivities do not directly cause weight gain but their effect on the body is certainly something to consider as you investigate your sudden weight gain. A food sensitivity is different from an allergy.

A food allergy has an almost instant effect on the body, causing swelling, itching, wheezing, nausea, and dizziness. They trigger an immune system response that is difficult to ignore.

Food sensitivities mainly manifest in the digestion system. Certain foods are harder for your body to digest which triggers a ripple effect throughout the body. Symptoms such as headaches, stomachaches, hives, gas, and bloating are common.

Common food sensitivities include gluten, dairy, eggs, caffeine, and soy. However, less common sensitivities to foods like tropical fruits, beans, chocolate, or coconut are not impossible. Sensitivities could be partly responsible for your weight gain because they cause inflammation. Systemic inflammation throughout the body affects our metabolism and fat burning.

8. Quitting Cigarettes

Most people gain weight when they quit smoking cigarettes. On average, when somebody quits smoking they gain between five and ten pounds. Cigarettes speed up the body’s metabolism, doubling the calories you burn. They also curb your appetite.

After you stop smoking, your metabolism slows back down. You may also feel hungrier and reach for food to replace the nicotine. The good news is the weight gain related to quitting cigarettes usually only lasts for about three years while the negative effects of smoking can last a lifetime.

9. Aging

While it’s a myth that you have to gain weight with age, aging does lead to declining muscle mass. Even people with a stable weight will experience a shift from muscle to fat over time. Muscle does not turn into fat. Instead, body fat percentage rises as muscle mass declines.

This change causes weight gain because fat is less metabolically active than muscle. So, if we continue to eat the same amount of calories while our muscles change to fat, our body will not burn them as quickly and the fat will begin to accumulate in the body.

Weight training is a great way to prevent age-related muscle loss. It keeps your muscles strong while also improving stability and balance. You need to do weight training at least three days a week to maintain muscle mass, five days if you are looking to add it.

If you decide not to add weight training to your fitness routine, you could also consider reducing your caloric intake or doing regular cardio to maintain a healthy weight.

10. Sleep Problems

If you often get fewer than six hours of sleep and notice marked changes to your appetite, your weight gain could be related to sleep problems. Sleep and weight gain are intricately connected. The surge in the prevalence of obesity has been closely followed by an upsurge in sleep troubles. Particularly, in terms of sleep quality. Increasingly, evidence shows that a lack of sleep or poor sleep quality escalates your risk of dramatic weight gain.

Lack of sleep also affects your:

  • Metabolism
  • Hormones
  • Glucose levels
  • Insulin tolerance
  • Stress
  • Cravings
  • Appetite

Sleep directly influences our relationship to food. You may have noticed that after a poor night of sleep, you reach for foods that give you immediate energy like candy, chips, and bread. When you do not get enough sleep, your body releases the hormone ghrelin and the production of the hormone leptin is put on hold. Ghrelin is the ‘go’ hormone that tells us when to eat, and leptin is the ‘stop’ hormone that tells us when we are full. So essentially, your hormones are controlling your cravings.

Investigating Weight Gain

You may have noticed that a lot of the unexpected causes of weight gain are related to each other. Hypothyroidism is a hormone imbalance that could be the result of a lack of sleep. Insomnia could lead to depression and alcohol abuse. Drinking too much can affect your hormones and metabolism. Most of the time, unexplained weight gain is more complicated than one cause.

Speak to your doctor if you believe your unexplained weight gain could be a result of one of the health problems listed above. The sooner you begin to address your weight problems, the better your health will be. Weight loss is a journey and you should not expect results overnight. Instead, focus on finding the root cause of your illness and you might be surprised by the results.

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