Vitamin D Deficiency Diet: What to Eat and What Food Can't Do

20 October 2026 · Irina Shtern · MSc Nutrition (Middlesex University) · BANT-registered nutritional therapist · CNHC registered

Food helps with vitamin D, but it rarely fixes a deficiency on its own. In the UK, 80-90% of vitamin D comes from sunlight on the skin and only 10-20% from food, so the sensible plan combines oily fish, eggs, mushrooms and fortified foods with a supplement and a blood test where your GP advises one. Below you will find which foods give the most, how to build a day of eating around them, and what to do if B12 is also low.

Foodconnection

Make Nutrition Guidance Personal

Food Connection creates personalized nutrition plans that consider your lifestyle and provide ongoing support for your health goals.

Visit Food Connection

TL;DR

Diet alone seldom corrects a true deficiency. The NHS advises considering 10 micrograms (400 IU) daily from October to March, and all year round if you are in a higher-risk group.
The richest foods are herring, salmon, mackerel and sardines, followed by eggs, fortified spreads and cereals, and UV-exposed mushrooms.
Take supplements with a meal containing some fat.
Vegetarians and vegans need a deliberate B12 plan: fortified foods or a supplement.
Treatment doses for a diagnosed deficiency are set by your GP or pharmacist, not by a food plan.

Why food only gets you part of the way
How deficiency is defined in the NHS
The best food sources of vitamin D
A day of eating that leans on vitamin D
Supplements: how to take them properly
If B12 is low too: foods and a vegetarian plan
Our perspective
Getting a plan that fits you
FAQ
Sources

Why food only gets you part of the way

Vitamin D is made in the skin when it is exposed to UVB sunlight. In Britain that process is weak from October to March, which is why the official advice is a daily 10 microgram supplement in autumn and winter. The British Heart Foundation notes that average UK intake from food is around 2 to 3 micrograms a day, well short of 10.

So a vitamin D deficiency diet is a supporting act. It matters for keeping levels up once they are corrected, for people who avoid supplements, and for the calcium and protein that work alongside vitamin D for bones.

How deficiency is defined in the NHS

Local NHS guidance uses blood levels of 25(OH)D. In South West London guidance, under 25 nmol/L is treated as deficiency, 25 to 50 nmol/L as insufficient for some patients, and above 50 nmol/L as sufficient for most. Check your own result with your GP, because thresholds and treatment pathways vary slightly between areas.

If you have bone pain, muscle weakness, or are pregnant, over 65, or have a gut condition affecting absorption, speak to your GP before self-treating. Do not take high-dose products without advice.

The best food sources of vitamin D

The BHF lists average values per 100g for common fish:

Food (100g)	Vitamin D (micrograms)
Herring, grilled	16.1
Salmon, steamed	9.3
Mackerel, grilled	8.5
Sardines, canned in brine	3.3
Tuna, baked	3.1

One portion of herring or salmon can therefore cover most of a day’s 10 micrograms. Beyond fish, the same source points to eggs (the yolk), mushrooms and fortified foods such as some cereals, spreads, plant milks and orange juice. Check the label, as fortification varies by brand. Mushrooms vary widely: those exposed to UV light contain much more than standard ones, and the pack usually says so.

Liver is rich in vitamin D but also in vitamin A. Avoid it in pregnancy, and ask your GP or dietitian before eating it often.

A day of eating that leans on vitamin D

This is an illustration, not a prescription:

Breakfast: a fortified cereal or porridge made with fortified plant milk, plus two eggs on wholemeal toast.
Lunch: sardines on toast with a side salad, or a mushroom omelette using UV-exposed mushrooms.
Dinner: grilled mackerel or salmon with potatoes and greens, once or twice a week. Herring or kippers make a good alternative.
Snack: yoghurt or a calcium-fortified alternative, since vitamin D and calcium work as a pair.

Oily fish is usually advised at one portion a week or more, with limits for some groups such as pregnant women, so check the NHS fish guidance for your situation. If dairy is a problem, our guide to a lactose intolerance diet shows how to keep calcium up. For the wider picture, see the bone health diet.

Supplements: how to take them properly

Vitamin D is fat-soluble. NICE CKS background is that taking it with a meal containing fat improves absorption, so a supplement swallowed on an empty stomach does less work. Take it with your largest meal, or with eggs, fish, avocado or nuts.

For a diagnosed deficiency, GPs commonly prescribe a loading course followed by maintenance. The BNF lists adult maintenance doses of 800 to 2000 units daily, but your prescriber decides the dose and duration. Higher-risk groups, including people with dark skin or who cover most of their skin outdoors, or rarely go outside, may need supplements all year. If you are working out how much sun matters for your bones, this guide to sun exposure and vitamin D explains the basics, though UK winter sunshine is too weak to rely on.

Sun in summer still helps. One NHS guideline suggests around 15 minutes a day, at least twice a week, while always avoiding sunburn.

If B12 is low too: foods and a vegetarian plan

Many readers searching for vitamin D foods are also checking B12, especially if they feel tired. B12 is found naturally in animal foods. An NHS haematology leaflet lists red meat, fish, shellfish, eggs, poultry, dairy, yeast extract, and fortified cereals, tofu and plant milks.

For vegetarians, eggs, milk, cheese and yoghurt do the work, so aim for a few servings daily. Vegans should rely on fortified foods several times a day or a supplement. The same leaflet quotes a Vegan Society recommendation of 10 micrograms daily if fortified foods fall short.

Deficiency is not always about diet. NICE guidance NG239 explains that it can come from low intake, from problems absorbing the vitamin linked to medicines or surgery, or both. If you have symptoms such as numbness, pins and needles or persistent exhaustion, ask your GP for a test rather than eating your way round it.

Our perspective

In clinic, we see two patterns. Some people have been told to “eat more oily fish” and see no change in their blood results, because the gap was too big for food. Others take a supplement and never look at what supports it: calcium, protein, magnesium, and a gut that absorbs fat properly.

We treat vitamin D as one piece of a picture. If you have digestive issues, fatigue, perimenopause or a limited diet, a low result may be a symptom of something else, and a food list will not solve it. That is why we work through your lifestyle, your history and, where useful, functional laboratory tests, then build a plan that fits your week rather than a generic leaflet. The aim is habits you can keep without stress.

— Irina

Getting a plan that fits you

If you have tried adding foods and supplements and still feel unwell, a personalised plan can save months of guesswork. Our initial consultation lasts one and a half hours and includes written personalised recommendations, at £150. A follow-up within 8 weeks is £120, and 12 weeks of dedicated support is £250. We also offer laboratory test analysis and interpretation, in London and online. Our practitioner holds an MSc in Nutrition and is BANT and CNHC registered.

FAQ

Can you correct vitamin D deficiency with food alone?

Usually not. Most UK vitamin D comes from sunlight rather than food, and typical dietary intake is only a few micrograms a day. Food helps maintain levels, but a diagnosed deficiency is normally treated with a supplement prescribed or advised by your GP.

What are the best foods for vitamin D?

Oily fish top the list: herring, salmon, mackerel and sardines. Eggs, UV-exposed mushrooms and fortified cereals, spreads or plant milks add smaller amounts. Read labels, as fortification differs.

Should I take vitamin D with food?

Yes. It is fat-soluble, so taking it with a meal that contains some fat helps absorption. Taking it on an empty stomach makes it less effective.

What is a good vegetarian diet for B12?

Build it on eggs, dairy, yeast extract and fortified cereals or plant milks. Vegans need fortified foods several times a day or a supplement. If you have symptoms, ask your GP for a B12 test first.