I had a hard time finding any information about the origins of seed cycling—but it’s a practice that is reasonably well known in naturopathic circles. The concept is, certain types of seeds (flax and pumpkin) promote estrogen during the follicular (first) phase of the menstrual cycle, and other types of seeds (sesame and sunflower) promote progesterone during the luteal (second) phase; therefore, if a woman consumes the former during the first half of her menstrual cycle (or what should be the first half of her cycle, if she’s irregular) and the latter during the second half of her cycle, the constituents of the seeds will help to regulate her.
Seed cycling is also closely connected to the phases of the moon—traditional wisdom has it that before electric lights, women menstruated at the new moon and ovulated at the full moon. This works out in terms of timing, because the cycle from new moon to new moon is about 28 days, and the textbook length of a woman’s cycle is also 28 days. But is this coincidence, or is there data behind it? Likewise, what does the data have to say about specific types of seeds promoting specific female hormones?
Phase 1: Flax Seeds and Pumpkin Seeds
I found the most data on flax seeds with respect to hormone balancing, and indeed, they’ve been a part of my protocol for hormone balancing for some time, as they help to balance estrogen metabolism. This effect is probably due to the lignan content. Lignans are also phytoestrogens, or estrogen-like compounds naturally found in foods. That’s probably the idea behind putting them in the first half of the seed cycle: phytoestrogens will boost estrogen if it’s low, and raise it if it’s too high.
To back up the idea of flax seeds’ hormone balancing prowess in general, in this study, daily ingestion of a tablespoon of flax powder improved ovulation, and lengthened the luteal phase (the second half of the cycle) for women taking it daily by improving the estrogen to progesterone ratios. (Then again, that’s the luteal phase–not the follicular phase, when flax seeds are recommended in seed cycling.)
Another possible hormonal benefit in flax is the very high concentration of omega-3 fatty acids. A tablespoon of flax has about 1.8 grams of omega 3s, which is pretty spectacular. Essential fatty acids help balance hormones by improving the health of the cell membrane, thereby improving hormonal signaling.
Finally, flax seeds are high in Alpha-Lipoic Acid, a terrific antioxidant. This is healthy in general, and it can specifically help with blood sugar control — relevant for a woman whose irregular cycles might be linked to PCOS.
Pumpkin seeds also contain lignans and are therefore also phytoestrogens, so they will have the same estrogen-balancing effects as flax seeds: raising too-low estrogen, and lowering too-high estrogen.
Pumpkin seeds are also very high in magnesium, containing about 37% of the daily recommended dose, and about 14% of the daily recommended dose of zinc. Serum levels of both magnesium and zinc are higher in the luteal phase in general, or should be. But, perhaps the idea here is that the body might need more magnesium and zinc during the follicular phase, since according to this study that is the time those minerals are lowest in the body.
Phase 2: Sesame and Sunflower Seeds
Sesame seeds are also high in lignans: the phytoestrogens that help with estrogen metabolism. Remember that phytoestrogens help to balance estrogen levels—during the second half of the cycle, you want estrogen levels to go down while progesterone rises. But lignans should theoretically work just as well during the second as the first half of the cycle, even though they are balancing in the opposite direction.
Sesame seeds are also high in omega 3’s, like flax—so these, too, will help with cellular signaling and cell membrane health.
Sesame seeds are high in fiber, containing a little over a gram per tablespoon. It makes sense that this would help balance hormones during the luteal phase of the cycle, as fiber is great for helping the body to eliminate toxins. In this case, the toxin to be eliminated is excess estrogen left over from the follicular phase of the cycle.
Sesame and sunflower seeds both are high in Vitamin E, which directly improves production of progesterone during the luteal phase. Sunflower seeds are especially high—1/4 cup (which, granted, is a lot) provides 82% of the daily Vitamin E dose.
Sunflower seeds are also high in selenium, which has been shown to increase progesterone concentrations.
The Moon and Menses
Confession: this was the part that felt a little “woo-woo” to me. But here’s what the data said: according to this study, a statistically higher percentage of women menstruate on or near the new moon, and ovulate on or near the full moon, than not. But, on the flip side, “on or near” is a window of 3-4 days, according to this study. If you add 3-4 days on either side, that’s a possible 8-day window. That window represents 29% of the month—and the study only shows that 28% of women menstruate in that window, compared to a much lower number randomly distributed throughout the rest of the month. So I’m not convinced that isn’t just a probability game.
That said, if a woman isn’t ovulating at all, you’ll be choosing your follicular and luteal phases at random if you’re going to try seed cycling anyway. Why not choose the phases of the moon? It’s as good an option as any.
All four of the seeds involved in seed cycling contain constituents that support hormone balancing. Several of them contain the same constituents. Is it better to cycle them, or to just consume a decent amount of all four of the seeds all month long?
I’m frankly not convinced that it matters that much, except for this one thing: there’s a lot to be said for intention. Our brains are very, very powerful. If you’re not having a normal menstrual cycle now, but a daily ritual focuses you on the intention of creating one, that effect likely should not be discounted.