There are multiple benefits to consuming flax seed, that I’ve discovered as I research the seeds used in seed cycling. 1) Fewer anovulatory cycles in normal cycling women, 2) longer luteal phase with higher progesterone/estradiol ratio, 3) reduced stress hormones and perception of stress, 4) a number of more general health benefits including improved lipid profile, reduction in risk of cardiovascular disease, decreased A1c in type II diabetics, and potentially cancer prevention. I will discuss the first three in this post – for an excellent review of the other health benefits, please see this article.
There are three major components in flax seed that are thought to have health benefits – the fiber (6% of dry weight), the lignan alpha-linoleic acid (20%), and the phytoestrogen precursor secoisolariciresinol diglucoside (SDG, 1%). One can consume either whole (ground) flax seed or lignan or SDG extracts. If you’re trying to recover your period I would recommend ground flax as the relevant studies were mostly performed with that rather than extracts. For other health benefits, I would suggest looking more closely at the studies (in this review, for example) to determine whether they used extract or whole flax (many used specific extracts).
Flax seed and menstrual cycles
Hormone levels and menstrual cycle parameters in women consuming 10g flax seed per day were examined for the duration of three menstrual cycles (comparing with three menstrual cycles in the same women where no flax was consumed but diet remained otherwise the same). For each woman, the second and third cycles were examined.
There were two important findings. First, there were no anovulatory cycles (0/36 cycles in 18 women) in women consuming flax seed compared with three anovulatory cycles during the control phase (3/36 cycles in 18 women, anovulation occurred in three different women).
Second, luteal phase when consuming flax seed was 1.2 days longer than with no flax seed consumption. I loved that this paper actually graphed the change in luteal phase between the flax/no flax cycles rather than just reporting averages: 1 woman had a shorter LP by 1 day, five women had no change, one had half a day longer LP, five had a 1-day longer LP, two had a 1.5-day longer LP, and one each had 2, 2.5, 3.5, and 4.5 day longer LPs! Both of these results suggest that daily flax seed consumption might be beneficial for women trying to regulate periods, and those with short luteal phases (another tool to add to the short LP arsenal!)
When hormone levels were examined, there were no significant changes in any hormones: estradiol in the early or mid-follicular phase, or progesterone or estradiol during the luteal phase. Testosterone levels during the mid-follicular phase were about 10% higher, a significant difference. The researchers speculated this might affect the luteal phase length. There were also 25% higher progesterone to estradiol ratios during the luteal phase (non-significant 10% higher progesterone and ~15% lower estradiol combined to give a significantly higher P/E2 ratio under flax seed consumption). This could potentially explain the longer luteal phases.
Flax seed and improved stress perception
Another set of studies seem to show positive effects of flax seed consumption on hormones associated with stress response, and this is where I think that flax seed might help those who are working toward recovering missing periods, but not there yet.
The first study I want to tell you about looked at stress markers in mice fed either a control diet, or one that contained a commonly used anti-depressant (imipramine), pomegranate peel extract or flax seed extract. After 50 days various hormones were measured – cortisol, epinephrine, and norepinephrine. Flax seed extract and imipramine showed similar levels of decrease in each of these hormones, which is great for someone trying to recover from hypothalamic amenorrhea / no period, as each of those hormones help suppress the hypothalamus – decreasing levels will only help get the hypothalamus going again!
35 postmenopausal women consumed different varieties of flaxseed containing varied levels of two active components SDG and alpha-linoleic acid. Blood pressure was used as a marker of stress, and all three types of flax seed reduced blood pressure during a frustrating cognitive task, in comparison with the same task without flax seed consumption (the study was a crossover design so some women took the test with flax seed first and without second, for others the order was reversed so the reduction in blood pressure was not due to having taken the test before.) All three varieties reduced plasma cortisol as well, but the Linola 989 variety with the highest SDG showed the highest reduction.
Flax seed recommendations
I started researching the effects of flax seed in the context of seed cycling. As I read the scientific literature I noted that there was not a single study that alternated seed types – all the medical literature I could find had people (or animals) taking one seed type consistently. Evidence on the other seeds included in “seed cycling” can be found here (pumpkin, sesame, and sunflower seeds) – in short, there is nothing to suggest value in changing between seed types.
Studies show flax alone has the potential to reduce stress hormones, and have positive effects both on the follicular phase (including ovulation) and the luteal phase of a menstrual cycle. Based on the reduction in stress hormones and perceived stress, along with other health benefits and no adverse consequences, I see no reason not to add flax seed to your arsenal as you work to restore missing menstrual cycles or to potentially help with normalizing menstrual cycles that are wonky for other reasons. Instead of making yourself crazy trying to figure out what seeds to take when, as one has to do with “seed cycling”, simply eating ground flax seed every day (the other seeds could be added as you like) might be beneficial. Note that as with other supplements, it is unlikely that taking flax alone, without increasing food intake, reducing high intensity exercise, and reducing stress will be successful. Check out No Period. Now What? for evidence and recommendations on how to do all this, or schedule a time to work with me directly.
This is the ground flax I use (Amazon US):
I don’t have a specific recommendation for a brand for those of you in the UK but here’s a good list – I like the cold-milled variety as the lignans are more stable. And here are some options if you’re in Canada.
I’d suggest 10g/d as a reasonable amount based on the study finding fewer anovulatory cycles and longer luteal phases. For other health benefits, again, please examine the specific literature to find the optimal form of flax to use and what dose.
Also, note that there have not been any detrimental effects found with flax seed so far for most people, but the recommendation is not to consume flax in large quantities while pregnant as studies in rats do show some negative effects (included in this review). I wouldn’t stress if you’re pregnant and have some, but probably best not to have daily.
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