CYP19A1, also known as aromatase, is an important enzyme that produces estrogen. By regulating estrogen levels, CYP19A1 affects a variety of processes in the body, including fat production and distribution, bone density, female fertility, and brain function. Estrogen deficiency is associated with diseases such as osteoporosis, hardening of the arteries, and Alzheimer’s. Furthermore, CYP19A1 gene variants are associated with migraines and the growth of estrogen-sensitive cancers. In this post, you will find information about aromatase function, gene variants, and natural substances that decrease its activity.
What is CYP19A1?
Aromatase (CYP19A1) is one of the cytochrome P450 monooxygenases (CYPs) .
Many CYPs eliminate toxins and drugs from the human body. However, some, like CYP19A1, are not involved in detoxification but in steroid hormone production.
CYP19A1 The Good
CYP19A1 is also involved in the sexual development of the brain . How the brain develops and functions depends on the levels of sex hormones it is exposed to.
Furthermore, CYP19A1 also affects cognitive function. It is implicated in reading, speech, and language . Estrogen has important roles in learning and memory by enhancing neuron structure and function .
CYP19A1 The Bad
Increased aromatase activity, resulting in higher estrogen, promotes the growth of estrogen-sensitive cancers.
CYP19A1 Gene Polymorphism
To date, hundreds of CYP19A1 variants have been identified .
Clinical features of CYP19A1 deficiency include:
- maternal virilization in pregnancy (male-pattern hair growth and other masculine physical traits) due to the excess of androgens and lack of estrogens coming from the fetus. These resolve gradually after giving birth .
- (in women) virilized external genitalia, hemorrhagic ovarian cysts in childhood, primary amenorrhea (absence of menstruation), no breast development, and decreased bone density .
- (in men) osteoporosis due to impaired bone mineralization. They also may have abnormal testis size and sperm production, metabolic syndrome-like stomach obesity, and insulin resistance .
Having rs10046 (T) increases CYP19A1 levels (resulting in more estrogen) .
On the other hand, C/C is associated with higher apo B, insulin, BMI, and HOMA index (2250 subjects) .
Patients with C may also be more prone to heart disease (189 subjects) .
rs1902584 A carrier women have a higher waist-to-hip ratio (they are more prone to obesity) (1241 subjects) .
C carriers among men (those with either T/C or C/C) have a 1.5 times higher risk of having a low bone mineral density (2392 subjects) .
rs1902584 T carrier women have a higher waist-to-hip ratio (they are more prone to obesity) (1241 subjects) .
Having A/A reduces the risk of rectal cancer (791 cases and 999 controls) .
The common rs4646 C variant increases estrogen levels and may predispose women to female pattern hair loss (955 subjects) .
Woman A/A carriers have a higher bone mineral density (256 subjects) .
Also, blood pressure was higher in men but lower in women with the G/G (218 patients and 225 controls) .
Women A carriers had a greater risk of having higher blood pressure (639 subjects) .
The C variant produces 10–20% more estrogen in postmenopausal women .
rs749292 produces 10–20% more estrogen in postmenopausal women .
rs700158 G variant is a risk factor for preeclampsia (a pregnancy complication) (286) .
RS11632903 and RS1902586
Increasing or Decreasing CYP19A1
These increase CYP19A1:
These decrease CYP19A1:
- Olive tree leaves  and olive oil 
- Curcumin 
- Apigenin 
- Naringenin 
- Hesperetin 
- Chrysin 
- Kaempferol 
- Capsaicin 
- Mango peel 
- Lemons and limonoids found in lemons 
- Mangosteen 
- Ginkgo biloba [43, 44]
- Sumac sorghum bran extract 
- Licorice flavonoid isoliquiritigenin [46, 47]
- Biochanin A, from red clover (Trifolium pratense) 
- Hop flavonoids xanthohumol, isoxanthohumol, and 8-prenylnaringenin [49, 50]
- Lager beer, alcohol-free beer, stout beer, and xanthohumol-rich stout beer 
- Red wine [38, 42]
- Resveratrol 
- Grape seed extract [51, 42]
- Tea [38, 42]
- Coffee 
- Cocoa 
- Collards (including cabbage and broccoli) 
- Tomato leaves 
- Stinging nettle root extract 
- Cigarette smoke and tobacco leaves 
- White button mushroom unsaturated fatty acids 
- Damiana (Turnera diffusa) 
- Piper cubeba , a type of pepper
- Mammea siamensis 
- Nelumal A, found in Ligularia nelumbifolia 
- Rhus verniciflua