Common Causes of Unexplained Weight Gain

Unexplained weight gain happens when a person puts on weight without increasing their calorie consumption or decreasing their level of physical activity.

Basically, when you're not trying to gain weight and yet you do, it's described as unexplained weight gain. Pregnancy, constipation, menopause, lack of sleep, slowing down of metabolism, abnormal growth, and fluid retention are common causes.

Some medications can also have side effects that can cause rapid, unintended weight gain. Most people gain weight at some point in their lives, and many also experience periods of weight loss. However, rapid weight gain with no other changes in lifestyle may sometimes indicate a more serious problem.

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Symptoms of Unexplained Weight Gain

Sometimes however rapid weight gain can be due to a medical condition (Image via Pexels/Pavel Danilyuk)

The signs and symptoms of unexplained weight gain can vary greatly from one person to the next and from one cause of weight gain to another. Bloating and abdominal pain are two symptoms that may accompany this type of weight gain.

Swelling is not limited to the belly but can manifest elsewhere in the body, even in the limbs (arms, legs, feet, or hands). If you experience any of the following signs, it's critical that you get medical attention right away:

• fever
• shortness of breath
• heart palpitations
• skin sensitivity
• sweating
• difficulty breathing
• changes in vision
• rapid weight gain

When these symptoms accompany unexplained weight gain, they can sometimes signal a serious condition.

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Common Causes of Unexplained Weight Gain

An increased intake of high calorie junk foods can also be responsible for rapid weight gain. (Image via Pexels/Pavel Danilyuk)

Check out some of the most common causes of unexplained weight gain:

1) Medication

Rapid weight gain is a common side effect of some medications. The Obesity Action Coalition reports that one side effect of some medications is weight gain of several pounds per month.

Some drugs used to treat, among other conditions, can cause rapid weight gain in some patients. Drugs that are used to treat are often responsible for unexplained weight gain:

• seizures
• diabetes mellitus
• arterial hypertension
• causes of mental illness and sadness

However, you should consult your doctor if you doubt that your medicine is responsible for your weight gain. Not talking to your doctor about stopping a medication you're on is not advisable.

2) Hormonal Changes

Some medications can also cause unexplained weight gain (Image via Pexels/Pixabay)

Sudden weight gain in women is often seen during a particular age. During the transitional period of menopause that most women experience between the ages of 45 and 55, they often undergo unexplained weight gain.

One of the hormones - oestrogen - that controls menstruation and ovulation in women begins to decrease as they enter their reproductive years. As oestrogen levels drop during menopause, periods no longer occur at that time.

The loss of oestrogen during menopause can lead to a spread of fat around the abdomen and hips. Check out this article on menopause weight gain: why it happens and what to do.

3) Fluid Retention

Fluid retention may be the cause of sudden, unexplained weight gain. The result is edema, a condition characterized by the accumulation of excess fluid that can manifest as a puffy appearance in the affected area.

Gaining weight in this way is possible for those who have heart failure, kidney disease, liver disease, or who're taking specific medications. Regardless of the absence of other symptoms, you should always report sudden or significant weight gain and fluid retention to your doctor.

4) Thyroid Disorder

Unexplained hair loss and weight gain can be a result of hypothyroidism (Image via Pexels/Skitterphoto)

The thyroid disorder, known as hypothyroidism can slow down the body's metabolism, leading to unexplained weight gain. Due to the effects of hypothyroidism on the kidneys, thyroid issues can also lead to fluid retention.

The list of hypothyroidism symptoms can be expanded to include:

• constant fatigue
• feeling cold
• constipation
• stiff joints and aching muscles
• dry skin and hair
• brittle nails

5) Cirrhosis

Cirrhosis can be indicated by unexplained weight gain and an enlarged abdomen. Fluid build-up in the abdominal cavity is a symptom of cirrhosis, a condition in which scar tissue replaces healthy liver tissue. Ascites is the medical term for this accumulation of fluid in an abnormal manner.

In addition to the above, other cirrhosis symptoms include:

• ankle swelling
• trouble breathing
• abdominal pain

If a person receiving treatment for ascites notices a weight gain of more than two pounds per day for three days in a row, they should seek medical attention.

6) Polycystic Ovary Syndrome (PCOS)

Those who suffer from polycystic ovary syndrome (PCOS) may discover that they are prone to unexplained weight gain. High levels of male sex hormones are produced by the ovaries when PCOS is present.

Additional PCOS symptoms include:

• Period irregularity
• hair growth on unwanted areas (like the face, chest, and abdomen), thinning hair, and hair loss
• acne
• development of unsightly patches of dark skin on one's chest, shoulders, and neck

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Although there's currently no known cure for polycystic ovary syndrome (PCOS), your doctor may suggest making changes to your lifestyle, such as increasing your physical activity and adopting a healthier diet, to alleviate some of the symptoms. Reducing symptoms may also be aided by hormonal medications.

To surmise, there's no single cause for either unexpected weight gain or weight fluctuations. Due to aging and behavioral changes, many put on weight over time. However, issues with the thyroid, kidneys, or heart can sometimes manifest as rapid weight gain.

Read about how constipation can make you gain weight.

Quick, unintentional weight gain is cause for concern and should prompt a visit to the doctor for diagnosis and treatment.