Does flaxseed help with mood swings during perimenopause?

Flaxseed may offer modest support for mood swings during perimenopause by working through several biological pathways at once, though the direct evidence specifically for mood is limited and the effects are unlikely to be dramatic. Understanding why mood swings happen during perimenopause helps explain how flaxseed might fit in.

Estrogen does not just regulate your reproductive cycle. It also interacts with serotonin, the neurotransmitter most associated with mood stability. Estrogen helps keep serotonin receptors sensitive and supports the production of serotonin in the brain. When estrogen drops and swings unpredictably during perimenopause, serotonin activity can become erratic, which is one reason mood feels harder to regulate during this time. Cortisol and sleep deprivation pile on top of this, creating a challenging combination.

Flaxseed addresses this through three pathways. First, its lignans, specifically secoisolariciresinol diglucoside (SDG), act as phytoestrogens. Once your gut bacteria convert them into enterolignans, these compounds can interact weakly with estrogen receptors. Some researchers think this mild estrogenic activity may help smooth out the hormonal fluctuations that drive mood swings, though the evidence for this specific effect is modest and most of the lignan research focuses on hot flashes rather than mood directly. Second, flaxseed is a good source of ALA, a plant-based omega-3 fatty acid. Omega-3s play a structural role in brain cell membranes and influence neurotransmitter signaling. Some research suggests omega-3 deficiency is associated with lower mood and that supplementation may support mood regulation, though again the ALA conversion to active forms is inefficient compared to fish-derived omega-3s. Third, flaxseed's fiber content supports the gut microbiome. Research on the gut-brain axis shows that gut bacteria influence mood partly through serotonin production, since roughly 90 percent of the body's serotonin is made in the gut. A fiber-rich diet feeds the beneficial bacteria that support this process.

What does the research actually say? Studies on phytoestrogens broadly, including lignans, and mood in perimenopause show mixed results. Some trials report modest improvements in emotional symptoms, while others find little effect. The evidence is not strong enough to say flaxseed reliably reduces mood swings, but the biological rationale is sound enough that it is a reasonable thing to try as part of a broader dietary approach.

For practical use, you need ground flaxseed rather than whole seeds. Whole seeds pass through your digestive tract undigested and release almost none of the lignans or ALA. Research examining hormonal and metabolic effects has typically used around 2 tablespoons of ground flaxseed daily. Stir it into oatmeal, add it to smoothies, or mix it into baked goods. Keep ground flaxseed in the refrigerator or freezer to prevent the fats from going rancid.

Flaxseed oil contains ALA but lacks most of the lignans and all of the fiber, which reduces its relevance for mood support specifically. If you use flaxseed oil, be aware that it has blood-thinning properties. If you take blood thinners or anticoagulants, check with your provider before adding flaxseed oil to your routine. Ground flaxseed carries much lower blood-thinning risk.

If you have or have had a hormone-sensitive condition such as breast cancer, endometriosis, or uterine fibroids, discuss flaxseed with your healthcare provider before significantly increasing your intake. Its phytoestrogen content means it interacts with hormone pathways, and your individual health history matters.

Expect a minimum of 6 to 8 weeks before noticing any change. Lignan effects on hormone metabolism build gradually as gut bacteria adapt and enteroligan levels accumulate. Combining flaxseed with other mood-supportive strategies, including regular aerobic exercise, consistent sleep timing, blood sugar management through regular meals, and stress reduction, tends to produce more meaningful results than any single food change.

See a doctor if mood swings are severe, interfere with daily functioning, or involve feelings of hopelessness or thoughts of self-harm. Perimenopause-related mood changes can sometimes tip into clinical depression or anxiety disorders that deserve professional evaluation and treatment. Hormone therapy, antidepressants, and therapy are all evidence-based options that may be appropriate depending on your situation.

The PeriPlan app (https://apps.apple.com/app/periplan/id6740066498) lets you log mood swings daily so you can spot whether patterns shift over time and identify triggers or trends across your cycle.

This content is for informational purposes only and does not replace medical advice. Always consult your healthcare provider about your specific situation.