Vitamin C for fertility

On this page

1. What is vitamin C?
2. Function and how it works
3. Fertility benefits
4. Recommended daily dose
5. Food sources
6. Cautions and contraindications
7. My Fertility Guide
8. Related pages

1. What is vitamin C?

Vitamin C (ascorbic acid) is a water-soluble vitamin that cannot be stored in the body, so regular daily intake is necessary. It is needed for over 300 metabolic reactions and is one of the most important vitamins for reproduction in both men and women. Vitamin C is also one of the most powerful water-soluble antioxidants, protecting cells from damage caused by free radicals (reactive oxygen species).

Although the recommended daily allowance (RDA) for vitamin C in many countries is around 60–90 mg, the dose required for optimal fertility support is considerably higher. Reference ranges and recommended intakes vary from country to country — always interpret guidance against the recommendations of your own healthcare authority.

2. Function and how it works

Vitamin C has several important roles in fertility:

1. Antioxidant protection. Vitamin C neutralises free radicals that would otherwise damage egg cells, sperm cells and the DNA they carry. It also recycles vitamin E, allowing the two antioxidants to work together.
2. Iron absorption. Vitamin C dramatically increases the absorption of non-haem (plant-based) iron from the gut. This is particularly important for vegetarians, vegans and women with heavy menstrual bleeding.
3. Collagen production. Vitamin C is required for the synthesis of collagen, which forms the structural framework of the ovarian follicle, the corpus luteum and the uterine lining.
4. Hormone production. Vitamin C is concentrated in the adrenal glands and is required for the synthesis of stress hormones and steroid hormones, including the precursors of progesterone.
5. Sperm DNA protection. Research has shown that vitamin C protects sperm DNA from oxidative damage and reduces sperm clumping (agglutination).

3. Fertility benefits

Research has confirmed several specific fertility benefits of vitamin C supplementation:

1. Reduces sperm DNA fragmentation, which is a common cause of male infertility and recurrent miscarriage.
2. Improves sperm count, motility and morphology.
3. Prevents sperm from clumping together (agglutination), which can otherwise impair fertilisation.
4. Supports a healthy uterine lining and corpus luteum function.
5. Improves implantation by reducing oxidative stress in the uterine environment.
6. Supports adrenal function in women under chronic stress, indirectly supporting progesterone production.

4. Recommended daily dose

For fertility support, I recommend a daily dose of 1 g (1,000 mg) of vitamin C. This is well above the RDA but below the recognised upper safe limit of 2,000 mg per day. The dose can be split between morning and evening for better absorption.

Higher doses (above 2 g per day) can cause loose bowels, indicating that more than the body can absorb is being taken — reduce the dose if this occurs. Buffered or liposomal forms of vitamin C are gentler on the stomach for those who experience indigestion.

5. Food sources

Vitamin C is found in most fruit and vegetables, including:

1. Citrus fruits (oranges, lemons, grapefruit) — but limit citrus once you have ovulated, as hesperetin in citrus can affect progesterone
2. Berries (strawberries, blueberries, raspberries, blackcurrants)
3. Kiwi fruit
4. Peppers (red, yellow, green)
5. Broccoli, Brussels sprouts and other green leafy vegetables
6. Tomatoes
7. Potatoes

Vitamin C is destroyed by heat and light, so eating fruits and vegetables raw or lightly cooked preserves more of the vitamin.

6. Cautions and contraindications

1. Doses above 2 g per day can cause loose bowels and abdominal discomfort.
2. Very high doses can increase the risk of kidney stones in susceptible individuals.
3. Vitamin C can affect some blood test results (including glucose and faecal occult blood) — inform your laboratory if you are taking high doses.
4. Discuss with your doctor before high-dose vitamin C if you have iron overload disorders (haemochromatosis), as vitamin C significantly increases iron absorption.
5. Always consult with a fertility specialist or your doctor before starting any new supplement regime.

7. My Fertility Guide

8. Related pages

• Fertility supplements directory
• Vitamin E — works synergistically with vitamin C
• Iron — absorption increased by vitamin C
• Alpha lipoic acid — recycles vitamin C
• Sperm DNA fragmentation
• Male infertility