Antioxidants: Essential Fertility Nutrients

Did you know that your antioxidant intake could affect your chances of getting pregnant? Antioxidants exert their beneficial effects by neutralizing free radicals (also known as reactive oxygen species) that can be damaging to DNA, protein, and other cell structures. Higher levels of oxidative stress have been found in women with PCOS, advanced maternal age, and in obesity – all of these conditions are also associated with infertility.

In a 2010 study comparing women going through in vitro fertilization (IVF) compared to controls (women not going through IVF), the women going through IVF had higher markers of oxidative stress and lower levels of antioxidants in their follicular fluid and blood. Specifically, levels of vitamins A and C were lower in the women going through IVF as compared to the controls. A third group of women going through IVF took a multivitamin supplement supplying antioxidants. In this group, there was no increase in oxidative stress while doing IVF and their levels of vitamins A and C were similar or higher to the levels observed in women not undergoing IVF (1).

Put more simply, IVF seems to create oxidative stress and deplete antioxidant levels. Taking a prenatal vitamin with antioxidants as well as increasing intake of antioxidants in your diet are important steps in reducing this oxidative stress.

In addition, in a study published just this month, increasing intake of antioxidants was associated with shorter time to pregnancy in women who were being treated for unexplained infertility. These results were pretty variable depending on BMI and age, but they provide some preliminary evidence that higher intakes of antioxidants may be beneficial for fertility. The findings were as follows: Increasing vitamin C intake was associated with shorter time to pregnancy in women with BMI < 25, and time to pregnancy was shorter with increasing beta-carotene and vitamin C intake in women with BMI ≥25 who were under age 35. For women ≥ 35 years, increasing vitamin E intake was associated with shorter time to pregnancy (2).

Taking a prenatal vitamin that contains beta-carotene, vitamin C, and vitamin E is a good idea to make sure you’re covering your bases. It’s also important to increase your antioxidant intake from food, so try these tips to ensure you’re getting plenty of antioxidants from your food:

1. Include vitamin C rich foods daily. Aim for at least 5 servings of fruits and vegetables daily to increase your vitamin C intake. Especially rich sources of vitamin C include broccoli, oranges, bell peppers, kiwis, kale, strawberries, and Brussels sprouts.

2. Eat vitamin E rich foods every day. It’s estimated that 90% of Americans don’t get enough of vitami^{n E (3)}, so working on incorporating this important antioxidant is essential. In addition, there is evidence that women with lower intakes of vitamin E during pregnancy have children with lower risk for ^{asthma (4).} Vitamin E rich foods include avocado, almonds, almond butter, sunflower seeds, hazelnuts, spinach, and leafy greens like Swiss chard.

3. Include beta-carotene rich vegetables like orange/yellow vegetables and leafy greens. (The chlorophyll in leafy green vegetables covers up the orange/yellow color of the beta-carotene.) Include at least 1 serving (1/2 cup cooked or 1 cup raw) of leafy greens every day such as spinach, kale, collard greens, or chard – not only for their beta-carotene content, but also for their othe beneficial nutrients like folate, vitamin K, and calcium. Orange vegetables to include are butternut or acorn squash, sweet potatoes, and carrots.

4. Eat a variety of the different colored fruits and vegetables. This can help you obtain a variety of different antioxidants contained in the pigments of different fruits and vegetables. Include these different categories of fruits and vegetables:

Red vegetables for the lycopene: tomatoes, watermelon, grapefruit, and red bell peppers.
Orange/yellow vegetables for the beta-carotene and lutein: butternut or acorn squash, sweet potatoes, carrots, or yellow squash.
Leafy greens for the chlorophyll: kale, broccoli, spinach, chard, collard greens, mixed greens, arugula, cabbage, green beans, or any other green vegetables!
Blue/purple fruits/vegetables for a variety of different flavonoids: blueberries, blackberries, red grapes, and eggplant.

Stay tuned for more helpful tips and recipes to increase your intake of antioxidant fruits and vegetables!

References
1. Ozkaya MO, Naziroglu M. Multivitamin and mineral supplementation modulates oxidative stress and antioxidant vitamin levels in serum and follicular fluid of women undergoing in vitro fertilization. Fertil Stertil. 2010;94:2465-2466.
2. Ruder EH, Hartman TJ, Reindollar RH, et al. Female dietary antioxidant intake and time to pregnancy among couples treated for unexplained infertility. Fertil Stertil. 2014;101(3):759-766.
3. Vitamin E: Linus Pauling Institute at Oregon State University. Available at: http://lpi.oregonstate.edu/infocenter/vitamins/vitaminE/. Accessed March 20, 2014.
4. Devereux G, Turner SW, Craig LC, et al. Low maternal vitamin E intake during pregnancy is associated with asthma in 5-year-old children. Am J Respire Care Med. 2006;174(5):499-507.