EndoFlex is an essential oil blend made by Young Living that’s marketed primarily for supporting the endocrine system, the network of glands that produces hormones throughout your body. The blend combines spearmint, sage, geranium, myrtle, German chamomile, and nutmeg in a sesame seed oil base. People use it topically on the neck and pulse points, most commonly with the goal of supporting thyroid function, balancing hormones, and boosting energy levels.
It’s worth noting upfront: no clinical trials have tested the EndoFlex blend itself for any health condition. What does exist is research on several of its individual ingredients, which gives some context for why users report the effects they do.
What’s in the Blend
Each oil in the formula brings different properties to the mix. Spearmint is the first listed ingredient, making it the most concentrated oil in the blend. Sage and geranium follow, both with long histories in herbal medicine related to hormonal health. Myrtle, German chamomile, and nutmeg round out the formula, and the whole blend is suspended in sesame seed oil as a carrier, which means it comes pre-diluted compared to many single essential oils.
Hormonal Balance and Spearmint
The strongest research behind any ingredient in EndoFlex involves spearmint’s effect on hormones, particularly in women with elevated androgen (male hormone) levels. In a 30-day study of 42 women with polycystic ovary syndrome (PCOS), drinking spearmint tea twice daily lowered testosterone levels while increasing luteinizing hormone and follicle-stimulating hormone, both of which are important for ovulation. A shorter five-day study in 21 women with hormone imbalances found similar shifts in hormone levels.
These hormonal effects have practical relevance. High androgen levels in women are linked to excess facial hair growth, and in one 30-day study of 41 women with PCOS, participants who consumed spearmint tea reported a reduction in facial hair. Animal research has also shown that spearmint essential oil specifically reduced testosterone, decreased ovarian cysts, and increased the number of viable eggs in rats’ ovaries.
There’s an important caveat here: these studies used spearmint tea taken internally, not a topical essential oil blend applied to the skin. How much of spearmint’s hormone-modulating compounds absorb through the skin in a multi-oil blend is unclear, so the effects may not translate directly.
Thyroid Support Claims
One of the most common uses people describe for EndoFlex is applying it to the front of the neck over the thyroid gland. The idea is that myrtle and the other oils in the blend may support thyroid function. Myrtle oil has been traditionally associated with thyroid health in aromatherapy circles, and some practitioners suggest it may help normalize both overactive and underactive thyroid function.
However, no published clinical studies confirm that applying myrtle oil or any essential oil blend to the neck improves thyroid hormone levels. If you’re taking prescription medication for a thyroid condition, essential oils can generally be used alongside those treatments, but it’s important to discuss this with your prescribing provider rather than substituting one for the other. Thyroid conditions require monitoring through blood work, and changes in medication should be guided by those results.
Other Reported Uses
Beyond hormonal and thyroid support, users commonly apply EndoFlex for a few other purposes:
- Energy and fatigue. The spearmint and nutmeg in the blend both have stimulating aromatic profiles. Some users report feeling more alert or less sluggish after applying the blend to pulse points, which is consistent with the general energizing effects of mint-family essential oils.
- Adrenal support. Some users apply EndoFlex to the lower back over the kidney and adrenal area. The reasoning follows the same endocrine-support logic, though no clinical evidence directly supports this use.
- Mood and stress. German chamomile is well known for its calming properties, and geranium has been studied for its potential to reduce anxiety. The combination of calming and energizing oils may explain why some users describe the blend as “balancing” rather than purely stimulating or purely relaxing.
How People Apply It
EndoFlex comes pre-diluted in sesame seed oil, which makes it gentler on the skin than many undiluted essential oils. The most common application method is dabbing a few drops onto the front of the neck, the wrists, or other pulse points. Some users also apply it to the bottoms of the feet or the lower back.
For people with sensitive skin, further dilution is recommended. A typical ratio is about 15 drops of the blend mixed into 10 ml of a carrier oil like coconut, jojoba, or additional sesame oil. Doing a small patch test on the inside of your forearm before applying it to your neck is a good practice, especially since sage and nutmeg oils can cause irritation in some people. Sage-containing blends are also generally avoided during pregnancy due to sage’s historical association with uterine stimulation.
What the Evidence Actually Supports
The honest picture is that EndoFlex sits in a space between traditional aromatherapy and modern wellness marketing. Some of its individual ingredients, particularly spearmint, have genuine research showing hormonal effects when consumed. Others, like myrtle for thyroid health, rely more on traditional use than clinical data. And none of the research tested this specific blend applied topically, which is how most people use it.
That doesn’t mean users who report feeling better are imagining things. Aromatic compounds do interact with the body through both skin absorption and inhalation, and the placebo-controlled spearmint studies show real hormonal shifts from that plant’s compounds. But the gap between drinking concentrated spearmint tea and rubbing a six-oil blend on your neck is significant, and the product shouldn’t be treated as a substitute for medical evaluation of hormonal or thyroid concerns.