Most people assume they’re getting what they need from their diet, but nutrient deficiencies are surprisingly common, even in the UK. These gaps can sneak up without obvious signs, but over time, they take a real toll. Here are 13 key nutrients that are often overlooked, and why it matters.
1. Iron
Iron helps your body move oxygen around, so if you’re low on it, you’ll likely feel tired, weak, and foggy, without knowing why. Iron deficiency is the most common worldwide, and in the UK, a big chunk of women and teens aren’t getting enough.
You might notice things like pale skin, brittle nails, or even frequent headaches. Red meat is the most absorbable source, but you can also find it in lentils, tofu, leafy greens, and fortified cereals—just pair it with something vitamin C-rich to help it absorb better.
2. Vitamin D
With long grey winters and indoor jobs, most people in the UK don’t get enough sunlight to produce vitamin D naturally. That’s a problem because this vitamin supports your immune system, bones, and mood. Deficiency can leave you feeling sluggish or achy, and in serious cases, it can weaken bones. Since food sources are limited, many people benefit from a daily supplement—especially between October and March, when sunlight’s scarce.
3. Iodine
Iodine isn’t something people often think about, but it’s essential for your thyroid—meaning it affects energy, mood, and metabolism. Without enough, you can end up with brain fog, dry skin, or even fertility issues. It used to come mainly from dairy and fish, but changes in farming mean levels have dropped. Plant-based diets can make it even harder to get enough, so keep an eye out and consider a supplement if you don’t eat much seafood or dairy.
4. Vitamin B12
B12 is all about keeping your nervous system healthy and your energy levels stable. But if you’re vegetarian, vegan, or over 60, chances are higher that you’re not getting enough. It’s one of those nutrients where the symptoms like brain fog, weakness, or numb fingers—can sneak up slowly. Fortified foods or supplements can help fill the gap, especially if your diet is mostly plant-based.
5. Folate (Vitamin B9)
Folate is especially important for people who are pregnant or planning to be—but even beyond that, it plays a big role in red blood cell formation and energy. Low folate can lead to fatigue or anaemia and can be risky during early pregnancy. Leafy greens, legumes, and fortified grains are all solid sources. If your meals are more convenience-based or low in veg, you could be running low without realising it.
6. Riboflavin (Vitamin B2)
This one’s essential for converting food into energy and keeping your skin and eyes healthy. Deficiency isn’t talked about much, but over half of UK adults may not be getting enough of it. Cracks at the corners of your mouth, sensitivity to light, or sore throat can be subtle signs. Dairy, eggs, lean meat, and mushrooms are solid sources—just don’t expect your multivitamin to always cover it fully.
7. Vitamin E
Vitamin E helps protect your cells from damage and supports your immune system. It’s fat-soluble, which means your body stores it, but it also means it doesn’t show up in many common low-fat diets. If you’re skimping on nuts, seeds, or healthy oils, you might not be getting enough. It won’t cause overnight issues, but long-term deficiency can mess with healing and make your immune system more sluggish than it needs to be.
8. Calcium
Calcium is crucial for bones, teeth, and nerve function. While most people associate it with dairy, a lot of adults (especially women) fall short, especially if they’ve cut back on milk and cheese. If you’re skipping dairy or eating mostly plant-based, check if your plant milks or juices are fortified. Leafy greens and tofu can also help, but it’s one of those nutrients where watching your intake pays off in the long run.
9. Selenium
Selenium’s a small but mighty nutrient—your body only needs a bit, but it plays a big role in thyroid health, immune function, and cell protection. And UK soil doesn’t have much of it, which means the food grown here might not either. Brazil nuts are the richest source—you only need one or two a week to meet your needs. If you’re low in animal products, or your diet is super local and plant-based, it might be worth keeping an eye on this one.
10. Zinc
Zinc is a multitasker—it helps your body heal, supports your immune system, and keeps your skin and gut in check. And yet, it’s one of the most commonly overlooked nutrients. If you notice more colds, slower wound healing, or loss of taste or smell, low zinc could be part of the problem. Meat, seafood, seeds, and whole grains are great sources. Vegetarians might want to consider fortified options.
11. Vitamin A
Vitamin A supports vision, skin, and your immune system. It’s easy to forget about it because it’s stored in the body, but if your diet is lacking in colourful veg or liver-based foods, you could be low. Night vision issues or frequent infections can be early signs. Carrots, sweet potatoes, leafy greens, and eggs are all great ways to stay topped up—and unlike supplements, they won’t risk overdoing it.
12. Magnesium
Magnesium helps with sleep, stress, muscle function and energy—basically, it’s everywhere in the body. But lots of people don’t get enough, and deficiency can feel like anxiety, insomnia, or unexplained fatigue. Whole grains, dark chocolate, nuts, beans, and leafy greens all help. If you’re regularly stressed, drink lots of caffeine or alcohol, or struggle to wind down, magnesium might be worth looking into.
13. Vitamin C
It’s not just about fighting colds—vitamin C helps with skin health, wound healing, and absorbing iron. Even so, recent data shows a quiet rise in scurvy and hospital admissions due to low levels in the UK. If you’re skipping fruit and veg, or living mostly off processed food, it’s easy to miss. Bell peppers, citrus fruit, strawberries, and broccoli are all top options—and a glass of orange juice can sometimes do more than you’d expect.
