A complete guide: Supporting gut health during your menstrual cycle

A complete guide: Supporting gut health during your menstrual cycle

Registered Nutritionist Aine Coleman shares her complete guide to help women support gut health during their menstrual cycle.
Caitlin Hall
by Aine Coleman
Registered Nutritionist (ANutr)

It comes as no surprise to most women that the health of our gut is closely linked to our menstrual cycle. Bloating. Constipation. Cramps. Gut health symptoms during different phases of our cycle are familiar experiences. To better understand how you can support your gut during your cycle, I’ve put together your complete and one-stop guide to menstrual nutrition.


What is the menstrual cycle?

The menstrual cycle spans an average of 28 days and is divided into two distinct phases. It commences on the first day of menstruation, which is referred to as day 1. The period between day 1 to day 14 is known as the follicular phase, whereas days 15 to 28 constitute the luteal phase. Ovulation typically occurs in the middle of the cycle, around day 14, while PMS or premenstrual syndrome generally occurs 5-7 days before the onset of menstruation. Although most people who experience some form of PMS each month, the severity of symptoms can vary significantly.


Menstruation (3-7 days)

During menstruation, the body is shedding the uterine lining, which can result in the loss of blood and other nutrients. It is important to eat a balanced diet that includes plenty of iron-rich foods, such as leafy greens, beans, and fortified cereals, to help replenish these nutrients. Additionally, staying hydrated by drinking plenty of water can help reduce bloating and other symptoms.


Important nutrients: Magnesium & Iron


Magnesium is mostly stored in the bones, muscles, and soft tissues, and can help with PMS symptoms like cramps. But you don’t need to rely on a supplement as there’s lots of foods that contain magnesium.

Food sources:

  • Dark Leafy Greens; kale, rocket, spinach
  • Almonds
  • Pumpkin Seeds
  • Flaxseeds
  • Cashews 

Magnesium supplements can interfere with some medications. It’s important to check in with your GP before starting higher dose magnesium supplements. Too much magnesium can cause loose stools so if you are supplementing make sure you are having the correct dosage.



The role of iron in the body is energy production, oxygen transport, and rebuilding of the blood, which is very important when you are menstruating as we can lose around 50-80mL of blood.

Iron comes in two forms; heme and non-heme iron. Heme iron is found mostly in animal products, beef, liver, lamb, oysters etc. Heme iron is more easily absorbed than non-heme iron.

Non-heme sources of iron; chickpeas,quinoa, kidney beans, fortified cereals, lentils etc. 

Tip of the day: vitamin C helps increase absorption of iron. For example, add peppers and broccoli to your curries, or kiwis and strawberries to your salads. Another thing to note with iron is that caffeine can inhibit absorption e.g. tea, coffee. Try to ensure that you refrain from having tea/coffee up to an hour before you sit down to eat.


The Follicular Phase (7-10 days after period ends)

During this phase oestrogen levels begin to increase once again and our pituitary gland releases follicle stimulating hormone (FSH) to prepare one of the ovaries to start maturing the follicles that will eventually turn into a mature egg. Eating a diet rich in whole grains, fruits, and vegetables can help provide the body with the necessary vitamins and minerals to support this process. Additionally, consuming healthy fats, such as those found in nuts and seeds, can help regulate hormone levels and reduce inflammation.


Important nutrients: Fibre & Omega 3

Fibre FIbre Fibre

The average person in UK has about 18g of fibre a day. The recommendation is 30g of fibre per day, and importantly, aim for a diversity of fibre too (up to 30 different plants per week).

Examples of fibre:

  • Wholegrains
  • Nuts & Seeds
  • Beans & Legumes
  • Fruit & Vegetables

Fibre fuels and nourishes our gut bacteria. This is why it’s so important to diversify our fibre intake. One scoop (10g) of myota’s Metabolic Booster gives you 9 ‘plant points’. A plant point is earned from each different type of plant that is consumed across the week.

What is the benefit of fuelling your gut microbiota?

  • Promote a strong and healthy gut lining
  • Enhance nutrient absorption
  • Prevent harmful pathogens from entering the bloodstream
  • Improve insulin sensitivity
  • Reduce inflammation in the gut and whole body
  • Promote serotonin synthesis (an important brain neurotransmitter associated with anxiety and depression)
  • Communicate directly with the vagal nerve (the gut-brain axis)
  • Reduce risk of colon cancer

Oestrogen is normally pulled from the bloodstream by the liver, which sends it through a small tube, called the bile duct and then into the intestinal tract. Fibre then soaks it up like a sponge and carries it out with other waste.

For some women, constipation typically happens in the luteal phase, however other women with gut issues such as IBS can experience chronic constipation all throughout their cycle. The issue with constipation is that when this happens, we’re not excreting the oestrogen that has been broken down and detoxified by the liver. This means that these hormones can potentially get recycled back into the body, which can lead to higher levels of oestrogen. Fibre is great to get things moving if you’re feeling constipated. Remember when you’re increasing fibre into your diet to make sure you’re kept hydrated throughout the day.


Omega 3’s

Omega 3 fatty acids play a vital role at this stage to help structure and function of the cells. Also help support the hair and skin as well as support oestrogen and testosterone production.

 Food sources:

  • Salmon
  • Mackerel
  • Sardines
  • Flaxseeds
  • Walnuts


 In this phase (approx day 14), oestrogen peaks, with luteinising hormone (LH) triggering ovulation. Our ovaries release a mature egg and your progesterone levels start to rise too as your body hopes to fertilise an egg during this stage of the cycle. Ovulation tends to happen roughly two weeks before we menstruate. If we don’t fertilise an egg this cycle, we move to the luteal phase. During this phase, it is important to continue eating a balanced diet that includes plenty of fruits, vegetables, and whole grains. Consuming foods that are high in omega-3 fatty acids, such as salmon and walnuts, can also help reduce inflammation and support reproductive health.


Important nutrients: Vitamin D & Zinc 


 An important mineral for supporting healthy ovulation and progesterone production.

Food sources:

  • Food sources
  • Red meat
  • Pumpkin Seeds
  • Egg yolks
  • Oysters
  • Dairy


Vitamin D

Vitamin D helps regulate menstrual cycles, ovulation, and the implantation of the fertilized egg. Supplementing with vitamin D has shown to decrease certain symptoms e.g. fatigue, which normally occurs in the luteal phase. It is recommended that the general population supplements with Vitamin D between October - March in the UK.

 Food sources:

  • Mushrooms leave your mushrooms near the window where they can absorb more vitamin D
  • Salmon
  • Milk & Fortified plant based milk
  • Eggs


Luteal Phase (10-14 days before the next bleed)

During the early luteal phase, progesterone is at its peak and oestrogen is also still high, so life can be feeling pretty good. In the second half of the luteal phase, if we haven’t fertilised an egg, oestrogen and progesterone levels begin to drop. This is where we can  start to experience PMS symptoms like mood swings, sore breasts, acne, headaches, bloating, and anxiety.  Eating fats at this stage can support skin health (I always get those lovely chins spots at this stage). It can help prevent breakouts but there are other factors to consider e.g. stress etc.

Also during the luteal phase insulin sensitivity is low which can make our metabolic rate increase significantly making fat utilisation predominant. Another important factor to be aware of is serotonins levels are low at this time. Low levels of serotonin has been linked with increased appetite and food cravings Menstrual cycle rhythmicity: metabolic patterns in healthy women | Scientific Reports. There are ways to manage your blood sugar levels by consuming complex carbohydrates that are full in fibre and combining them with some fat and protein. Example: wholegrain bread with chicken, hummus (add a scoop of myota) and salad.

 Food sources:

  • Avocado
  • Salmon
  • Sunflower seeds

The menstrual cycle is a complex process that can be influenced by a variety of factors, including nutrition. A balanced diet that includes all of the essential macronutrients and micronutrients is important for maintaining overall health and can also impact the menstrual cycle. People who have irregular menstrual cycles or amenorrhea should talk to their healthcare provider to determine if nutritional deficiencies or imbalances may be contributing to their symptoms.



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