Weight gain during your period is a common symptom of menstruation.
If you struggle with your weight during the time of the month, then you may be wondering: “When does period weight go away?”
Hormonal fluctuations during the menstrual cycle have a huge impact on your physical and emotional wellbeing.
Tender breasts, constipation, fatigue, acne, mood swings, cramps – these are just some of the PMS symptoms that many women experience during their period.
Weight gain can also an unwelcome side effect of your period.
In this guide we’ll look at the reasons behind weight gain during your period and answer some of your common questions.
We’ll look at:
- What happens to your body during your period?
- Do you gain weight during your period?
- Does bloating cause weight gain?
- Are there any other causes of weight gain during your period?
- When does period weight go away?
- Do you burn more calories on your period?
- Period weight gain Q&A
- How to prevent period weight gain
Let’s get started!
What happens to your body during your period?
Your period (menstruation) is when your body discards the monthly build up of the lining of your uterus.
During the menstrual cycle, the lining in your uterus thickens to prepare for pregnancy.
Throughout this monthly cycle, a number of sex hormones necessary for reproductive health are sent around the body.
These changing hormone levels also result in menstrual symptoms such as breast tenderness, cramping, fatigue and acne.
If you do not get pregnant, the hormones estrogen and progesterone begin falling and trigger the start of your period.
As a result, blood and tissue are released from your uterus and pass out of your body through your vagina.
Your period marks the first day (day 1) of your menstrual cycle.
A typical menstrual cycle is 28 days long. Some women are even able to predict their period starting date month to month.
However, depending on the individual and time of the year, a menstrual cycle can last anywhere between 24 to 38 days.
Do you gain weight during your period?
Weight gain during your period is normal.
How much weight can you gain on your period?
Typically, you can expect to gain between 3 to 5 pounds during your period. It’s not unheard of to gain up to 7 pounds.
This weight gain is caused by hormonal fluctuations in the body which cause water retention.
In the days leading up to your period, tissues in your body accumulate more water due to these hormonal fluctuations.
Water retention, also known as edema, causes weight gain as well as swelling in parts of the body such as the legs and feet.
Does bloating cause weight gain?
Weight gain, or more accurately the feeling of weight gain, can also be caused by bloating.
Bloating is a common symptom of your period.
Although bloating may make you feel as if you have gained weight, it isn’t considered true weight gain and it’s essentially a build up of gas and air in your stomach.
You will likely experience bloating in the week leading up to your period and during the first few days of menstruation.
Stomach cramps are also a common side effect of your period.
Are there any other causes of weight gain during your period?
Other causes of weight gain include:
- Gastrointestinal issues
- Decreases in magnesium
There’s no doubt that the hormonal fluctuations during your period can make you overeat.
Your progesterone levels increase before your period starts.
Progesterone makes your appetite stronger, so you may end up eating more food than normal which can cause weight gain.
Constipation, diarrhoea, abdominal pain – these are all common symptoms that go hand in hand with your period.
Progesterone can cause slow digestion and constipation.
When your period begins, prostaglandins are released by your uterus which cause muscle contractions in your uterus and gut.
All of these changes cause pelvic and abdominal pain.
Decreases in magnesium
During your period, your magnesium levels drop which make you crave sugar.
Magnesium is a mineral in the body that regulates your body’s hydration status.
Low levels of magnesium can cause dehydration.
When you’re thirsty, you may mistake this for hunger, causing you to overeat or eat high calorie or sugary foods which can cause weight gain.
When does period weight go away?
When does period weight go away?
Assuming the weight gain is caused by water retention, your weight should return to its normal range within 3 to 5 days after your period starts.
Do you burn more calories on your period?
The amount of calories you burn during your period will depend on a variety of factors.
Namely your resting metabolic rate (RMR), which is the amount of calories your body burns while at rest.
Your RMR is affected by your age, gender, health, diet, race and activity levels.
Research has found that resting metabolic rate varies widely across women during the menstrual cycle.
In a 2003 study, they tracked the resting metabolic rates in 19 women during one complete menstrual cycle. The study found that:
- 9 women had a wide variation of changes to their RMR – between 5-10%
- 10 women had hardly any change at all to their RMR – between 2-4%
The study concluded that RMR cannot be assumed to be stable in all women.
The key takeaway? Some women may burn more calories on their period while others won’t have much of a difference.
Period weight gain Q&A
Q: When does period weight gain start?
A: Weight gain typically starts during the luteal phase of your menstrual cycle.
The luteal phase starts after ovulation – typically day 15 or 16 of your menstrual cycle.
Q: Do you weigh more on your period?
A: Everyone experiences period weight gain differently.
Typically if your period causes water retention, you can expect to weigh more on your period.
However, weight gain can also caused by your diet, especially if you eat high calorie foods.
Q: How much weight gain is normal during your period?
A: Research tells us that you can gain up to 7 pounds during your period.
7 pounds in kg is 3.17 kg.
However, typically you can expect to gain between 3 to 5 pounds.
Any more than this may be a sign of an underlying health issue so if you have any concerns, check with your doctor.
How to prevent period weight gain
Now you know the answer to: “When does period weight go away?”
Here are some tips on how to prevent period weight gain.
#1 Eat a healthy diet
High fibre foods and complex carbs like sweet potatoes and whole wheat foods are your best friends during your period.
Fibre helps to absorb water in your gut which you then poop out, helping to prevent water retention and bloating.
Complex carbs also help to reduce any sugar cravings as they don’t have a huge impact on our blood sugar levels.
Avoid foods high in salt (sodium) as these can cause bloating and weight gain.
#2 Stay hydrated
By drinking plenty of water you will help to flush your system of things like sodium which can cause bloating and weight gain.
One 2021 study concluded that water intake may have a role in reducing menstrual bleeding duration, pain killer utilisation and pain intensity during your period.
Although you may feel like exercise is the last thing you want to do during your period, it can help to move fluid around your body.
Aim to do at least 30 minutes of aerobic exercise 3 or 4 times a week.
Aerobic exercise like walking, running, cycling and swimming are great options during your period.
Hormonal fluctuations can cause you to feel tired, so you may want to adjust the intensity level of whatever exercise you do in the days leading up to your period and during your period.
#4 Take magnesium supplements
A magnesium supplement will help to ease bloating and period cramps during your period.
Taken daily, magnesium works by relaxing the muscles in the uterus and reduces prostaglandins that cause period pain.
#5 Take diuretics
Diuretics (also known as water pills) help to rid your body of sodium and water.
Typically, they are used to treat high blood pressure, but can also be prescribed by a doctor to ease water retention during your period.
Speak to your doctor for more information.
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