10 Medical Conditions Causing Weight Gain: When to Consult Your Doctor

Explore the blog post revealing 10 medical conditions that could be behind unexpected weight gain. Learn when it's crucial to consult your doctor for a deeper understanding of your health.
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Our body is constantly changing.

We may have times when we feel bloated, like when we are on our period, or we may have times when we feel lean, especially if we have been following a healthy lifestyle and exercising regularly.

However, unexpected weight gain or loss can be concerning and sometimes the symptom of an underlying health condition.

Here are 10 medical conditions that can cause weight gain

1. Hypothyroidism

10 medical conditions that can cause weight gain - and when you need to see your doctor

Your thyroid is a gland that can be found in your neck and it is responsible for producing hormones and controlling your metabolism.

When your thyroid isn’t working properly it can affect your metabolism and in some causes cause weight gain. You may also feel cold, tired, constipated or have irregular periods.

If you suspect you have a thyroid issue, we advise you speak with your medical practitioner ASAP.

2. Polycystic Ovary Syndrome (PCOS)


Typically, women with PCOS struggle to maintain a heathy weight while at the same time, women who gain weight can experience PCOS.

According to a study by Monash University, PCOS is the most common hormone problem among women in the fertile age group, affecting six to 21 per cent of women.

7 tips to reduce belly fat if you have PCOS

3. Insomnia

10 medical conditions that can cause weight gain - and when you need to see your doctor

Research reveals that a lack of sleep or insomnia can lead to weight gain. These changes in our sleep cycles can affect our eating patterns as well as our mood and cause people to overeat.

A recent study found that sleep-deprived people ate more carbohydrates to meet their energy needs, and this ultimately led to weight gain.

4. Diabetes

10 medical conditions that can cause weight gain - and when you need to see your doctor

Weight gain is a common side effect for people who suffer with type 2 diabetes. People who are overweight are also more likely to develop type 2 diabetes.

Many people take insulin to help manage their diabetes as insulin helps to control your blood sugar level.

Those who have diabetes also tend to eat more than they need to prevent low blood sugar, also known as a ‘hypo’ or hypoglycaemia.

5. Irritable bowel syndrome 

How to reduce belly fat if you suffer from PCOS, under active thyroid & IBS

Irritable Bowel Syndrome  (IBS) can often cause constipation due to an inflammation in the bowels which causes it to move more slowly than normal.

IBS can cause weight gain or loss depending on the individual.

The exact causes of IBS are unknown. However, a diet of eating several small meals over the course of the day, as well as a diet high in whole grain carbs can be very beneficial.

6. Certain medication

10 medical conditions that can cause weight gain - and when you need to see your doctor

Certain medications may cause people to gain weight rapidly. Medication for seizures, diabetes mellitus, high blood pressure or depression may cause some people to pile on the kilos in a short space of time.

Do not stop taking your medication without discussing with your doctor first.

7. Quitting smoking

10 medical conditions that can cause weight gain - and when you need to see your doctor

Many people find they become heavier when they quit smoking cigarettes.

On average, people gain 2 to 5 kilos in the months after they give up and many feel put off quitting if they are worried about adding extra weight.

But not smoking is one of the best things you can do for your health and you can always lose weight after you quit. It’s harder to fix damaged lungs.

Speak with your doctor if you need nicotine patches to help you quit.

8. Pregnancy

10 medical conditions that can cause weight gain - and when you need to see your doctor

This one seems like an obvious one, but not all women know straight away if they are pregnant!

You may find you’re putting on weight, eating more, sleeping more or even feel nauseous in the first few months while you are expecting.

We advise you take a pregnancy test and see your doctor if you suspect you are pregnant.

9. Heart problems

losing weight after pregnancy

People suffering with heart problems or heart failure may notice rapid changes in their weight.

If you suspect you are having heart problems we advise you speak to your doctor or head to the emergency department at your hospital STRAIGHT AWAY!

10. Stress

10 medical conditions that can cause weight gain - and when you need to see your doctor

Stress may lead to a change in eating habits and can cause an increase in cravings for unhealthy food.

Hormonal changes triggered by stress may cause weight gain or affect changes in metabolism, insulin and fat storage.

If you have any concerns about your medical health or unexplained weight gain then we advise you speak with your GP as soon as possible.

How to reduce belly fat if you have PCOS, an under active thyroid or IBS

Sleep, stress and obesity: What our Global Mums Health Survey told us

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