Learn about causes of weight gain, self-help treatment options, medication and when to seek medical help
Article last reviewed 23
January
2025
10 mins read
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What is Weight Management?
There are many tips and advice for how to prevent weight gain and/or reduce your weight. This article will cover medications and supplements which may help you to manage your weight.
What are the possible causes of being overweight?
The most common reason for weight gain is when you consume more calories than your body uses on a day-to-day basis. The amount of calories that your body needs daily will differ based on your gender, age and activity level. You may refer to a calorie calculator such as the one on Healthhub (Make Healthy Food & Grocery Choices (healthhub.sg)) to find out your ideal caloric intake.
Certain factors may also cause you to gain weight more easily:
Quitting smoking: During the initial stages of quitting smoking, your metabolism slows down and your appetite increases. However, in the long run, quitting smoking will have a greater benefit on your health
Eating out frequently: Food from restaurants and hawker centres generally have more oil, sugar and fats
Pregnancy: While weight gain is expected in pregnancy, the decrease in ability to move around and pregnancy cravings for food may cause some women to gain more weight than is necessary and face difficulty losing it after giving birth
Lack of sleep: Your body produces more ghrelin (hunger inducing hormone) and less leptin (hunger suppressing hormone) when you lack sleep, leading to an increase in appetite
Ageing: As you age, your metabolic rate decreases, your ability to move around and energy level may also decrease, leading to lower activity levels.
Social and economic factors: Your job and lifestyle may prevent you from having the time to exercise or to prepare healthy, home-cooked meals.
Weight gain may also happen as a result of a medical condition. A small percentage of people have genetic conditions that cause them to gain weight easily. Other medical conditions such as depression, polycystic ovary syndrome, diabetes, hypothyroidism and Cushing’s syndrome may also cause you to gain weight quickly.
Finally, several medications can also increase your risk of weight gain. Some examples of these include but are not limited to:
Birth control pills
Insulin
Oral steroids
Anti-depressants
Anti-psychotics
Beta-blockers
Sulfonylureas
What are the symptoms of being overweight?
We use the Body Mass Index (BMI) to tell if you are overweight. This is calculated as body weight in kilograms over height in meters squared. For Asians in Singapore, the table below shows the BMI categories:
BMI = Weight (kg) / [Height (m)]2
Category
<18.5
Underweight
18.5 - 22.9
Normal
23.0 - 29.9
Overweight
≥ 30
Obese
Do note that BMI is less accurate as a measurement tool for those who are very muscular, in people with a condition known as sarcopenia, children and pregnant women.
What medications and supplements can I use to lose weight?
The main method to lose weight involves changing your lifestyle to reduce your caloric intake and increase your activity level. However, if you are obese (BMI ≥ 30), or overweight (BMI ≥ 28) and have a history of high blood pressure, diabetes or high cholesterol, you may approach a pharmacist to get a medication which reduces the absorption of fat from the food that you eat.
Orlistat
While there are many supplements being sold to help to lose weight, do note that none of them have enough studies to prove their effectiveness. Most of these supplements claim to work by:
Increasing the metabolism of fat cells (african bush mango, green tea, raspberry ketone)
Increasing the metabolism of carbohydrates (green tea, green coffee, raspberry ketones, alpha lipoic acid)
Do also note that some of these supplements may have potentially harmful side effects. For example, supplements containing senna, a kind of laxative, may cause diarrhoea that leads to potentially dangerous dehydration (losing too much water from the body). Do consult your healthcare professional if you are in doubt as to whether a supplement is safe to consume for weight loss.
Finally, do take note that healthy weight loss should be no more than 0.5 to 1kg a week. Losing weight too quickly can lead to:
Dehydration
Electrolyte imbalance
Loss in muscle mass
Slowing down of metabolism
Poor nutrition
Irregular menstrual cycles
Osteoporosis (in the long run)
When do I need to see a doctor?
Although healthy weight loss may be achieved without a doctor’s consultation, there are times where the condition might be more serious.
If you suspect your weight gain may be due to a medical condition or medication, speak with a doctor to determine how to manage it appropriately. Never stop a long-term medication abruptly without first consulting your doctor.
You may also consult a doctor if you feel that you require further medical assistance to lose weight.
What else can I do to manage this condition?
Lifestyle changes are very important in weight management. Two lifestyle changes you should try to include:
Reducing your caloric intake
Use the calorie counter in HealthHub to calculate your daily caloric intake
Have a healthy and balanced diet which does not exceed your recommended caloric intake
Refer to tools such as My Healthy Plate when planning your meals
Refer to nutritional labels and choose food and drink options which are lower in fats, salts and sugar
Increasing your physical activity level
If you have a long-term medical condition, check with your doctor if you are fit and able to increase your activity level
Start slow and increase the intensity of your activity gradually
Choose exercises which are conveniently located and fun for you so that you will be able to continue the activity in the long run
Aim to have a mix of cardio and strength building exercises
For cardio exercises, aim to reach at least 150 minutes of moderate intensity exercise per week
For strength building exercises, aim to do them on at least two days per week, with at least one day apart (not two days in a row).
Disclaimer
This article is jointly developed by members of the National Medication Information workgroup. The workgroup consists of cluster partners (NHG Health, National University Health System and SingHealth), community pharmacies (Guardian, Unity and Watsons) and Pharmaceutical Society of Singapore. The content does not reflect drug availability and supply information in pharmacies and healthcare institutions. You are advised to check with the respective institutions for such information.
The content above is solely for informational purposes only and is not intended as a substitute for the advice provided by your physician, pharmacist or other healthcare professional. You should not use the information for diagnosing or treating a health problem or disease, or prescribing any medication or other treatment. Always speak with your physician, pharmacist or other healthcare professional before taking any medication or supplement, or adopting any treatment for a health problem.
There are many fun and exciting ways to embark on a healthy lifestyle and reap the benefits of physical activity without having to spend a ton of money. Engaging in at least 150-300 minutes of moderate-intensity aerobic activity weekly can help prevent Type-2 diabetes, heart disease and high blood pressure. Check out these 4 low-cost yet fun ideas that can get you moving!
The Recommended Dietary Allowances (RDA) refer to the recommended daily levels of nutrients to meet the needs of nearly all healthy individuals in a particular age and gender group