It happens every single month, without fail. You start to feel moody, low and irritable, and you notice a big increase in hunger (and your cravings for chocolate and ice cream). And when you finally get your period, all you can think about is getting into your PJs and eating more comfort food.
For most women, these sudden changes in appetite and mood are normal, something we listen and adapt to. But why do we feel more hungry around our period, really?
We automatically think it has everything to do with hormones, but it's actually much more than that.
"There's certainly some evidence that women do get hungrier and crave sugar and sweet things, primarily chocolate, leading up to their period in the premenstrual or luteal phase of their cycle," Dr Clare Ballingall, a GP and chair of RACGP Tasmania, told The Huffington Post Australia.
There are many theories as to why this happens, Ballingall said.
"We do know the hormone changes that occur, so oestrogen and progesterone go up and then they drop off just before the period, and this is a theory for increased hunger," Ballingall explained.
"The other thing is we know that women possibly become a bit more responsive to insulin in that premenstrual phase. Some women can experience mild alterations in their blood sugar and cravings for chocolate, that's a possible theory.
"Women also often get irritable and cranky premenstrually, and there's a theory that somehow eating chocolate increases serotonin and dopamine, which are involved with helping 'prop up' mood."
Nutritionist Pip Reed agrees, saying that the occurrence of PMS or PMT symptoms can lead us to reach for foods which boost our energy and mood.
"Often this hunger is for more carb and sugar heavy foods as we may find the rise in oestrogen increases PMS symptoms, including irritability, stress, anxiety. So we're therefore looking for foods that will give us a quick energy boost," Reed told HuffPost Australia.
"Interestingly, the main paper I looked at, which had the most women involved in, there was no increase in cravings for salt and fast food in that same period. Women eat more leading up to that period, and they sleep less, which is interesting," Ballingall added.
Beyond physiological reasons for increased hunger around menstruation, Ballingall also said there are psychological and cultural factors at play here.
"Psychology Today theorised that culturally we've reinforced chocolate as being a way to deal with stress, through media and subliminal advertising," Ballingall said.
"They suggested that in a society we, as women, are told to avoid fat and sugar, and that we're all guilted into having this certain body type image and we must maintain that.
"But somehow it's culturally acceptable for one time a month to just let yourself go and reward yourself with chocolate as you're feeling a bit crap because it's your period. Culturally we accept that, where any other time of the month it's unacceptable to binge on chocolate."
There's also the fact that treating ourselves to chocolate, getting in our comfies and cosying up in bed with a feel-good movie, really does make us feel good. We're allowing ourselves to relax and indulge in foods we often ban or restrict ourselves of.
"Absolutely. Chocolate makes you feel good, that's a proven thing. That melting feeling in your mouth, the sugar hit, the energy hit," Ballingall said.
Given that women make up around 50 percent of the world's population, there is surprisingly little scientific research into women's health issues surrounding the menstrual cycle.
"There's not actually a lot of journal work done around this area suggesting why this happens, which I think is remarkable," Ballingall said.
If you are experiencing PMS symptoms and increased hunger and food cravings, try these four tips.
1. Be kind to yourself
If you're feeling low, moody and hungry, instead of resenting yourself for it, be kind to yourself.
"I have a lot of women who get really bad PMT. There's lots of issues dealing with that," Ballingall said.
"I reinforce that cultural message of: don't beat yourself up about it because there's a lot of things women feel guilty about anyway."
If chocolate and ice cream is what you want and they make you feel better, then have them in appropriate amounts.
"Everything in moderation is fine. To calorie restrict on your premenstrual phase is a miserable thing to do," Ballingall said.
"Just generally be kind to yourself more than anything. There's still this 'periods are bad', 'periods are taboo' and 'periods are somehow getting rid of the toxins', and people still believe all that. Try to normalise it as much as possible."
2. Do gentle exercise and eat well
Along with that delicious chocolate, try to do gentle exercise like walking or yoga, and remember that eating healthily will actually make you feel better.
"I spend a lot of time talking to women about eating well and doing a bit of exercise, especially in the premenstrual period," Ballingall said.
"For those who want the treat but still want to eat healthy, choose high fibre natural foods such as dates and walnuts, raw nut treats like caramel slice, and add cinnamon to breakfast and afternoon yoghurt snacks for blood sugar stabilisation," Reed told HuffPost Australia.
"Choose dark chocolate varieties over milk for antioxidants and anti-inflammatory properties. Pana Chocolate or Loving Earth are made with coconut nectar and taste amazing."
Focus on choosing whole grain versions of refined pastas, breads and snacks.
"[Choose] whole grain versions such as quinoa, sourdough, rye, amaranth or buckwheat instead which contain more nutrients, are high fibre and won't cause blood sugar spikes," Reed said.
"Also make sure you have good healthy fats and protein such as avocado, nuts, seeds, fish and chia seeds to fill you up and decrease inflammation."
3. See a GP
If your PMS or PMT symptoms are affecting your day-to-day life, including your concentration or your mood to the point where you feel depressed, see your GP for help.
"A lot of women get really bad PMT. Looking at their mood, we sometimes offer a cyclical antidepressant where some women take them in the two weeks leading up to their period and then stop," Ballingall said.
"That's accepted treatment now for people who have true PMT which is interfering with their lives."
4. Don't compare yourself to other women
The worst thing you can do is compare yourself to that other woman who doesn't get PMS or the friend who glides through their period without any weight gain, increased hunger or pain.
"That's where our job is hard -- there's no one size fits all," Ballingall said. "My endeavour every day is for them to take on one simple healthy eating and lifestyle tip, whether it's on their period or not. But also to be kind to themselves."
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