Vegetarianism, veganism, and the menstrual cycle
Does being vegan or vegetarian affect your period?
Top things to know about veganism and your cycle
There is not enough conclusive research to show how plant-based diets impact the menstrual cycle.
A varied, nutrient-rich plant-based diet that meets daily caloric needs is just as likely to support a regular cycle as any other diet.
Vegan or vegetarian diets may need additional iron-rich food, especially if you have a heavy period.
If you notice any cycle changes after changing how you eat, talk to your doctor.
People choose to avoid meat or animal products for a variety of reasons, from ethical concerns to health benefits. Some simply prefer to eat less meat and emphasize plants in their diet.
Research suggests that a well-planned vegetarian or vegan diet can be appropriate at any stage of life as long as all nutrient needs are met (1). Eating more plant-based foods can decrease the risk of some chronic health conditions like diabetes, cancer risk, and heart disease (2).
But how does eating a primarily plant-based diet affect your menstrual cycle? The truth is that studies on how diet impacts the menstrual cycle are lacking overall, but we have some clues from existing research.
Cycle Length and Plant-Based Diets
There's little evidence to suggest that eating or avoiding meat will change a person's menstrual cycle. The high number of variables related to the menstrual cycle (or any health outcomes) makes things more complex, and more focused research is needed.
A person's diet can impact menstrual cycle length when foods or food groups are restricted if it leads to a lower overall intake of calories (3). Extreme caloric restriction can affect cycle length or stop menstruation altogether (3).
A plant-based diet that meets daily caloric needs and contains a variety of nutrient-rich foods is just as likely to support a regular cycle as any other type of diet. In some circumstances the motivation for a dietary change is an important healthcare consideration – especially if that motivation stems from a desire to reduce caloric intake (4). Whether choosing to follow a plant-based or any other dietary pattern, what matters most is meeting nutrient and calorie needs to support overall health.
Note: If you are concerned about disordered eating habits (meaning any habits that are restrictive, compulsive, irregular or inflexible) you can find support through NEDA here.
Nutrients from plant-based diets could help premenstrual symptoms
There is minimal research to suggest that plant-based diets affect premenstrual symptoms, as most available studies are observational, which means that they can’t establish a cause-and-effect relationship, but there are a few worth examining.
One study found that following a low-fat, vegan diet for two cycles significantly decreased premenstrual pain duration and intensity, possibly due to the increased fiber intake (5).
Following a plant-based diet could help you identify particular foods (or food groups) which may be contributing to PMS symptoms through the process of elimination. Dairy, for example, is excluded or limited in many plant-based dietary patterns.
Anecdotally, some people find that reducing or eliminating dairy decreases cramps or other PMS symptoms, but other research suggests the opposite (6). One study found that women who eat more skim or low-fat milk have a reduced risk of developing PMS, possibly related to the extra calcium and vitamin D in the milk (6).
There is evidence that magnesium and calcium could help reduce menstrual cramps (7, 8). These nutrients are found in foods emphasized in a plant-based diet like leafy greens, nuts, and seeds (9, 10).In other words, there's no one-size-fits-all answer to whether or not a plant-based diet affects your period.
Following a diet pattern that works best for your lifestyle while emphasizing nutrient-rich foods like fruits, vegetables, and other high-fiber foods may be the best approach—with or without meat.
Iron deficiency and menstruation
Iron deficiency means the blood has less than ideal levels of the mineral iron. The amount of iron in your blood is important because it helps your body create hemoglobin, a substance in red blood cells that carries oxygen around the body (11). When you don't have enough iron in your blood, it can lead to anemia, which means you don't have enough oxygen-rich blood flowing through your body (11).
If you are living with iron deficiency anemia you might notice fatigue, feeling cold when other people don’t, restless leg (itching, crawling, or pulling sensations in the legs), feeling like you can’t catch your breath, unusually pale skin (pallor) or very pale pink or yellowish coloring on the inside of the lower eyelids, nails that break more often than they used to, and suddenly losing more hair than you do usually(12).
People with a menstrual cycle are more likely to have anemia than those without a cycle, regardless of what diet they follow, because of blood loss during their period (13). Losing any amount of blood means your body loses red blood cells.
Studies suggest that people who follow plant-based diets could be more at risk for iron deficiency or low iron stores (14, 15), but this doesn't mean all vegetarians and vegans will experience iron deficiency.
Iron found in meat (called heme iron) is more bioavailable, which means it's easier for the body to absorb (16). Plants contain a less bioavailable form called non-heme iron (16). Both forms of iron can benefit your body.
Even though there's plenty of iron in plant-based foods, our bodies might not be able to use it as effectively, so people who rely on these foods may need to eat more to get enough (17).
In other words, eating a plant-based diet doesn't automatically mean someone will become anemic, but including iron-rich foods, especially if you have a heavy menstrual cycle, might protect your red blood cell supply. These foods include (18):
Dark leafy greens like kale and spinach
Beans and legumes including kidney beans, navy beans, and black beans
Lentils and chickpeas
Tofu
Dried fruits
Nuts and seeds
Iron-fortified cereals
Vitamin C also helps your body absorb more of the iron in your food. If you are eating plants that are high in iron, also eating vitamin C-rich foods like citrus fruits or bell peppers can help with iron absorption (16). You can also cook in a cast iron skillet, as this adds small amounts of iron to food (19).
Sometimes iron supplements are needed, but it's best to speak with your doctor before starting any supplement. Taking an iron supplement can help you meet your needs if you have low iron, but taking too much or when you don’t need it can have side effects like upset stomach, constipation, or diarrhea, and even organ failure if taken in very high doses (20).
Track of your cycle to learn how your body responds
The effect of any diet really depends on the individual. The best way to know how your diet affects your period is to keep track of changes in your cycle. Tracking your flow along with your emotions, sleep, energy, digestion, and state of mind may add context to what's happening with your body.
Cycle changes, especially unpredictable or absent periods, are important to pay attention to. If you adjust your diet and notice menstrual cycle changes, it's always a good idea to talk to your doctor or a registered dietitian to ensure your nutrient needs are met.
Download Clue to track your digestion, cycle length and other menstrual experiences to better understand your body’s unique patterns.