Preconception Nutrition: Where to Start (and What Actually Matters)

If you've started reading about nutrition for fertility, you've probably noticed two things. First, everyone has an opinion. Second, almost none of those opinions come with references. That's exhausting when you're already carrying the weight of trying to conceive.

Here is a straightforward, evidence-based starting point — the things that actually matter in the three months before trying for a baby, without the noise.

Why the three months before matter

A woman's eggs take roughly 90 days to mature before they are released at ovulation. Sperm take around 70 to 90 days to develop. This means the nutritional environment in the roughly three months before conception genuinely influences egg and sperm quality — not just in theory, but in measurable ways that show up in fertility research.

This is good news. It means you have real, meaningful time to make changes before trying, and those changes have a biological window to do their work.

The five things that genuinely matter

1. A predominantly Mediterranean-style eating pattern

The most consistent evidence in fertility nutrition doesn't point to any single "superfood." It points to an overall pattern. Mediterranean-style diets — rich in vegetables, fruit, whole grains, pulses, olive oil, fish, and modest amounts of dairy and poultry — are associated with better fertility outcomes in both natural conception and IVF.

This isn't about perfection. It's about the shape of your week. If most of your meals include vegetables, whole grains, and a protein source, and olive oil is your main fat, you are already most of the way there.

2. Folic acid, before you need it

The UK recommendation is 400 micrograms of folic acid daily, starting at least one month before conception and through the first trimester. Some women need a higher dose (5 mg) — including those with a higher BMI, diabetes, epilepsy on certain medications, or a previous pregnancy affected by neural tube defects. This is worth a conversation with your GP before you start trying.

Folate from food (leafy greens, pulses, fortified grains) is important but does not replace the supplement.

3. Vitamin D, worth checking

Most UK adults are deficient or insufficient in vitamin D for at least part of the year. Low vitamin D is associated with reduced fertility and less favourable IVF outcomes. The NHS recommends 10 micrograms daily for all adults from October to March, and year-round for those with limited sun exposure.

If fertility is actively a focus, asking your GP for a blood test is reasonable.

4. Iron, quietly

Low iron stores are common in women of reproductive age and have been linked to ovulatory problems. You don't need to megadose; you need to know your iron status and address it if it's low. Red meat, pulses, and dark leafy greens help, especially paired with vitamin C to improve absorption.

5. What to reduce, not eliminate

The evidence is clearest on reducing a few things rather than adopting restrictive diets:

• Alcohol — ideally stopping well before trying
• Caffeine — most guidance suggests keeping it under 200 mg daily (around two small cups of coffee)
• Ultra-processed foods as the everyday default
• Trans fats — largely phased out of UK food, but worth checking labels of imported baked goods

Note the word "reduce." The stress of perfectionism around food is itself not helpful for fertility.

What the evidence does not strongly support

This part matters because it saves you money and anxiety. The following are popular online but are not well supported by the current evidence base as meaningful drivers of fertility in otherwise healthy women:

• Eliminating gluten or dairy when you don't have a medical reason to
• Specific "fertility diets" sold as programmes
• Most single-nutrient supplements beyond folic acid, vitamin D, and (where indicated) iron
• Detoxes, fasting, or cleanses in the run-up to trying

This doesn't mean they don't help individual people. It means the evidence doesn't support recommending them to most women trying to conceive.

Male partners matter too

Roughly half of fertility challenges involve a male factor, and sperm respond to nutrition and lifestyle within about three months. Partners should be eating the same broadly Mediterranean pattern, limiting alcohol, not smoking, keeping caffeine moderate, and taking a basic multivitamin with zinc and selenium if their diet isn't consistent. This is genuinely half the picture, and too often ignored.

A realistic way to start

You don't need a complete overhaul. Pick three things this week:

• One extra portion of vegetables at each main meal
• A folic acid supplement starting today
• An honest look at alcohol and caffeine

That's a better starting point than a complicated plan you abandon in a fortnight.

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If you'd like personalised support

I'm a UK-registered dietitian (HCPC, BDA Full Member) specialising in fertility and women's health, with both NHS experience and lived experience of IVF. If you'd like to talk through where to focus your own preconception nutrition — whether you're just starting or already deep into the journey — book a free 15-minute call or read more about how I work with fertility clients.

There's no pressure on the first call. It's a conversation, not a sales pitch.