If you’ve been exploring women’s hormone wellness online, you’ve likely come across articles touting the miracles of seed cycling for regulating the menstrual cycle. In case you missed it, seed cycling is a protocol where you consume specific seed combinations during distinct phases of the menstrual cycle in order to balance female hormones. The excitement is understandable. The promise of a simple, food-based solution to heal your hormonal woes is certainly compelling. However, overall, the science on seeds does not support the claims that are being made – eating this or that seed at a certain time in your cycle doesn’t regulate your hormones. Have a listen to this latest episode of Natural MD Radio, or read the article below.
The Seed Cycling Fad: Overstated Evidence
Seed cycling is, without a doubt, a fad that showed up on the women's wellness scene as it began to blossom on the internet, less than 10 years ago. A quick internet search will easily yield you a dozen of articles from online ‘women's wellness experts' extolling its benefits. It's a meme of sorts. One person made it up. Then a whole lot of copy cats just kept repeating the message. Over and over until it seemed like there must be something real to it.
Sorry to be snarky, but that's how these things take hold.
The logic of seed cycling is as follows: By eating certain seeds at different phases of your cycle (i,e. certain seeds during the first half, or follicular phase, and others during the second half, or luteal phase), the varying lignan (phytoestrogen), fatty acid, and micronutrient constituents of those seeds will provide the optimal hormonal support at the right time, and will effectively ‘balance; your estrogen and progesterone levels. However, these are conjectures and generalizations based on an incomplete understanding of plant/food chemistry and hormone physiology. These effects haven’t been demonstrated, and hormone levels take more than a week of eating this or that food to alter.
The body does mobilize nutrients differentially across the phases of your menstrual cycle (zinc, magnesium, and calcium blood levels have been shown to vary across the cycle), but this does not mean that there's any benefit to shifting seed intake accordingly across the cycle to somehow supply these nutrients to match shifting amounts. Our brilliant bodies tightly regulate how nutrients are utilized, and additionally, nutrient stores accumulate over time, and usually necessitate larger quantities and longer time frames of regular use than occur in the seed cycling protocol.
Further, and importantly, most of the ‘data’ that is mentioned in seed-cycling articles, and referenced in those few that even bother to include references, is based on completely out-of-context studies in dairy and beef cows who have had induced or in vitro implanted pregnancies, who are lactating, and other parameters that don’t relate to eating seeds throughout the menstrual cycle. Each study also focuses on giving these animals very large doses of one or two of the same types of seeds daily, for weeks or months at a time – and most find very minimal, if any, relevant hormone changes. Thus, seed-cycling, like so many wellness trends is a well-marketed, oft repeated myth. In this case, it's a harmless one or the most part if you're using it preventatively, but it is, nonetheless, misleading.
Why do some women say it works? Well, most things work for 30% of people who try them; that's the standard placebo response. Second, adding anything healthy to your diet, including seeds, usually leads to overall dietary conscientiousness and small positive nutrition shifts can be beneficial for your nutrition and thus well-being. Third, if you haven't caught onto this by now, there are a lot of exaggerated claims on the internet – including success stories.
There is a Seed of Truth
Like so many wellness fads that take hold, there is, excuse the pun, a seed of truth, which is why these logical-sounding approaches seem to make so much sense. In this case, it's true that seeds are part of an overall healthful diet, and some may have a slight hormonal impact. For example, studies show that:
- Vitamin E and omega 3- and omega-6 fatty acids, which are found in flax seeds, sesame, pumpkin, and sunflower seeds are essential for hormone production and ovarian follicular function.
- Zinc, present in meaningful concentrations in pumpkin and sesame seeds, helps to improve the formation of the corpus luteum, progesterone levels, and gets the endometrium prepped for implantation.
- Seeds are rich in selenium which supports ovulation and fertility, as well as liver detoxification phases.
- And lignans, which flax and sesame seeds are especially rich in, are converted to enterolactones in the presence of healthy gut flora, which help keep your estrogen levels healthy.
But seed cycling does not have any clinical studies to support it, and any studies that show any hormonal impact of consuming seeds uses the same seeds daily and consistently for weeks to months at a time, in much greater quantities than in seed cycling, in which minimal amounts are consumed for short, rotating periods of time – quite the contrary to the science behind using seeds for hormonal impact.
So should you bother eating seeds? Absolutely!
Seeds that Support Hormone Health (and How to Use Them)
There is some science behind the benefits of specific seeds for hormone health – just not seed cycling. Let's take a look at which seeds are important for your health, and which may have some added hormonal health perks.
Studies have shown that consumption of flax seeds does both increase luteal phase length and reduce the number of anovulatory cycles, as well as improving your progesterone to estrogen ratio in the luteal phase. What does this mean? Flax seeds may increase the likelihood of regular ovulation and improve progesterone levels as a result. So if you’re skipping periods, or have low progesterone, adding flax to your diet through the month is a great choice. They may also reduce excess estrogen levels.
Beyond its direct impact on the menstrual cycle, flax has additionally been found to both decrease stress hormones and decrease stress perception (your subjective sense of stress levels). This impact on the HPA axis (hypothalamic pituitary adrenal axis) and the stress response in general could presumably have positive downstream effects on your cycle as stress is one of the overarching signals that most influences sex hormone levels. After menopause, they also have protective effects against breast cancer. Beyond their beneficial hormonal effects, flax is also a superstar for your overall health. In additional to its sex hormone effects, it has also been shown to reduce cardiovascular risk profile, decreasing A1C levels in type 2 diabetes, making them a great addition to your diet if you have PCOS with insulin resistance or elevated blood sugar.
How to use them: Most of these studies tested 10g of flax a day; I recommend women consume 2 tbsp. of ground flax daily, which is a bit above this amount, and also gives you a healthy dose of fiber. Sprinkle on your cereal, add to your smoothie, or use as a salad topping.
Sesame seeds have also been shown to influence female hormones in a way that may be particularly useful for the hormonal profile of women suffering from PCOS. Specifically, one study (in menopausal women) found that eating 50g of sesame seeds daily for 5 weeks decreased DHEAS significantly (by 18%) and increased SHBG significantly (by 15%). Since SHBG levels are often low in PCOS patients (contributing to elevated androgen levels) and DHEAS levels elevated, sesame seeds are worth bringing into your daily routine if you have PCOS. One of the simplest and most delicious ways to incorporate sesame seeds into your life is by using organic tahini butter (a seed butter made from ground sesame seeds). Also, if you use tahini, because it is so concentrated, all you need is 1 to 2 tablespoons at a time; otherwise you’d need to get ¼ cup of seeds at a time, or more. My Open Sesame Nuggets (recipe at the end of this article) are a great way to get more sesame, and other seeds into your daily routine.
Pumpkin and Sunflower Seeds
And don’t forget about pumpkin and sunflower seeds: They also contain important micronutrients for overall nutritional health and should also be incorporated into your diet on the regular. Sunflower, sesame, flax, and pumpkin seeds all have high levels of micronutrients and fatty acid profiles that have been shown to positively impact overall health which itself can be beneficial for your menstrual cycle. For example, zinc, which is highest in pumpkin and sesame seeds, may increase the formation of the corpus luteum and support healthy progesterone levels in the second half of the cycle, and at least in mouse studies, low zinc is associated with poorer ovarian egg development and blocked ovulation. However, based on the available studies, there’s no evidence that sunflower seeds are more beneficial than flaxseeds, and the studies looking at sunflower seeds show minimal if any impact on hormone levels, with perhaps a slight increase in progesterone seen in just some of the studies, but not all.
Reclaim your power. Feel at home in your body. And be the force of nature you really are!
Seed Cycling: The Bottom Line
If you have PCOS, you might consider adding sesame seeds to your daily diet. If you have missing periods or general menstrual irregularities, flax is a wonderful, daily-use, nutritional ally for you.
Rather than spend your precious life energy stressing about eating the “right seeds” at “the perfect time,” you can let go of the rigidity and instead choose to consume a variety of seeds daily (the more often, the better). The best way to incorporate these into your diet is liberally, on a regular daily basis as a part of your overall healthy diet and lifestyle, rather than in a regimented way.
Ah, doesn’t life feel simpler already?
If you find the structure of seed cycling to be a useful strategy in order to help you get a diversity of seeds in your diet in an organized manner, there are no harmful effects – but don't expect any hormone balancing miracles from following the seed cycling protocol. It's purely sexy wellness hype.
Not for the Birds Seed Recipes
I eat some seeds almost every day and have for decades. I love sprinkling toasted ‘sunnies' or roasted ‘pepitas' (pumpkin seeds) into a salad, I include seeds in my granola recipe, and add tahini to just about everything – it's my favorite spread on toast, and as a topping on steamed veggies, and grains.
Here are a couple of seed recipes to enjoy any time of your cycle!
Open Sesame Nuggets
Put the following ingredients into your food processor with a chopping blade in place:
- 2/3 cup of a combination of sesame, sunflower and pumpkin seeds, plus optionally, your choice of almonds or walnuts
- 4 pitted medjool dates OR 2 tbsp. good quality honey
- 2 tbsp. tahini (sesame seed butter)
- ¼ cup or so of coconut flakes
- Optional: 2 tsp. of any of your favorite adaptogen or medical mushroom powders, ground flax seeds, or dark cocoa powder
Blend until well mixed, but you still see some bit of nuts and seeds. Remove from food processor, shape into balls using about 1 tbsp. of dough per ball, and roll in some extra raw or toasted coconut flakes, or sesame seeds.
Land & Sea Vegan Nosh
If you’re food adventurous, want to add a healthy burst of trace minerals – especially thyroid-healthy iodine – to your diet, and like the salty briny taste of seaweed, you’re in for a treat with this long-time favorite snack of mine.
- 2 sheets of dried, toasted Nori seaweed or ¼ cup of toasted, crumbled dulse leaves (to prepare, place about 1/3 cup dried dulse seaweed onto a cookie sheet and bake at 300 degrees F for about 10 minutes, or until you can easily crumble it).
- ½ cup of pumpkin seeds, sunflower seeds, shells removed, or a mix
- Gluten free tamari (soy sauce)
- Garlic powder
- Tear the Nori into bite-sized pieces, or crumble the dulse, and place into a bowl
- Toast seeds in a cast iron or stainless steel skillet (low heat, until the pumpkin seeds start to ‘pop’ or the sunflower seeds look lightly golden brown, takes about 3 minutes; take care not to burn by stirring while toasting)
- Sprinkle the toasted seeds, still in the skillet, with 2 tsp. tamari
- Toss with ¼ to ½ tsp. garlic powder
- Mix in with the seaweed
- Eat warm or cool
- Store in an airtight container when fully cooled to room temperature.
- Will last for weeks in the container.
For more variations see my Savory Nuts and Seeds recipe.
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