Signs You Might Be Vitamin Deficient

How Common Are Vitamin Deficiencies in the UK?

The UK has a well-documented problem with certain nutrient deficiencies. Data from the National Diet and Nutrition Survey (NDNS) and NHS England paints a clear picture:

These are not rare or exotic conditions. They affect millions of people across the UK, and many do not know they are affected until symptoms become significant.

Vitamin D Deficiency: The UK’s Most Widespread Gap

Vitamin D is unique because your body produces it when sunlight hits your skin. In the UK, between October and March, the sun is too low in the sky for your skin to make any vitamin D at all — regardless of how long you spend outdoors.

Symptoms to watch for

• Bone pain or achiness — Particularly in the lower back, hips, legs, and ribs. Vitamin D is essential for calcium absorption, so low levels can lead to softened bones.
• Muscle weakness — Difficulty getting up from a chair, climbing stairs, or general feelings of physical weakness, particularly in the thighs and upper arms.
• Persistent fatigue — Tiredness that does not improve with adequate sleep. Several studies have linked low vitamin D to reduced energy levels.
• Frequent infections — Vitamin D plays an important role in immune function. Catching every cold going around can be a sign.
• Low mood — There is a well-documented association between low vitamin D and seasonal low mood, particularly during winter months in the UK.

Iron Deficiency: More Than Just Tiredness

Iron deficiency is the most common nutritional deficiency worldwide, and the UK is no exception. It is particularly prevalent in women of reproductive age due to menstrual blood loss, and in people following plant-based diets where iron is less readily absorbed.

Symptoms to watch for

• Persistent fatigue and weakness — The most common symptom. Iron is needed to produce haemoglobin, which carries oxygen in your blood. Less iron means less oxygen delivery to your tissues.
• Pale skin and pale inner eyelids — Reduced haemoglobin gives skin a washed-out appearance, most noticeable on the face, inner lower eyelids, and nail beds.
• Shortness of breath — Especially during physical activity. Your body struggles to transport enough oxygen when iron is low.
• Brittle nails — Nails that chip, crack, or develop a spoon-shaped concavity (koilonychia) can indicate iron deficiency.
• Restless legs — An uncomfortable urge to move your legs, particularly at rest. Research has linked restless legs syndrome to low iron stores.
• Frequent infections — Iron supports immune function. Recurrent infections can be an overlooked sign of deficiency.
• Hair thinning or hair loss — Iron deficiency can disrupt the hair growth cycle, leading to increased shedding, particularly noticeable at the parting.

Dietary sources of iron

Red meat, liver, and shellfish provide haem iron, which is readily absorbed. Plant sources like lentils, chickpeas, spinach, and fortified cereals provide non-haem iron, which is absorbed less efficiently. Eating vitamin C-rich foods (peppers, tomatoes, citrus) alongside plant iron sources significantly improves absorption.

Vitamin B12 Deficiency: Often Missed

B12 is essential for nerve function, red blood cell production, and DNA synthesis. Unlike many vitamins, your body can store B12 for several years, which means a deficiency can develop very slowly and go unnoticed for a long time.

Symptoms to watch for

• Extreme tiredness — Beyond normal fatigue. B12 is needed to make red blood cells; without enough, you develop megaloblastic anaemia.
• Tingling or numbness — “Pins and needles” in your hands, feet, or legs. B12 is crucial for maintaining the myelin sheath that protects nerve fibres.
• Mouth ulcers and a sore, red tongue — Glossitis (a swollen, smooth, red tongue) is a classic but often overlooked B12 deficiency sign.
• Cognitive changes — Difficulty concentrating, memory problems, and a feeling of “brain fog.” In older adults, severe B12 deficiency can mimic dementia symptoms.
• Mood disturbances — Depression, irritability, and anxiety have been linked to low B12 levels in some studies.
• Balance problems — Nerve damage from prolonged B12 deficiency can affect coordination and balance.

Who is most at risk?

• Vegans — B12 is found almost exclusively in animal products. Without fortified foods or supplements, deficiency is virtually inevitable on a vegan diet.
• Older adults — Stomach acid production decreases with age, reducing B12 absorption from food.
• People taking certain medications — Proton pump inhibitors (omeprazole, lansoprazole) and metformin can reduce B12 absorption over time.
• People with digestive conditions — Crohn’s disease, coeliac disease, and other conditions affecting the small intestine can impair absorption.

Other Deficiency Signs Worth Knowing

Folate (vitamin B9)

Symptoms overlap significantly with B12 deficiency: fatigue, weakness, and mouth sores. Folate is particularly critical during early pregnancy — deficiency increases the risk of neural tube defects. Good sources include leafy greens, fortified bread (mandatory in the UK since 2024), and pulses.

Zinc

Frequent colds and slow wound healing can indicate low zinc. Other signs include loss of taste or smell, skin rashes, and poor appetite. Zinc is found in meat, shellfish (especially oysters), nuts, seeds, and wholegrains.

Magnesium

Muscle cramps (especially at night), restless legs, difficulty sleeping, and anxiety can be associated with low magnesium. Many UK adults do not meet the recommended intake. Good sources include nuts, seeds, dark chocolate, wholegrains, and leafy greens.

Calcium

Calcium deficiency often shows no obvious symptoms until bone density has already decreased. Long-term low intake increases osteoporosis risk. Muscle cramps, numbness in fingers, and dental problems can be early indicators. Dairy, fortified plant milks, canned fish with bones, and kale are good sources.

Iodine

Iodine deficiency can cause fatigue, weight gain, dry skin, and feeling cold. It is essential for thyroid function. UK intake has been declining, partly due to reduced dairy consumption. Milk, yoghurt, fish, and seaweed are the main dietary sources.

When to See Your GP

Many vitamin deficiency symptoms overlap with other conditions, so self-diagnosis is not reliable. See your GP if you experience:

• Persistent fatigue that does not improve with adequate sleep and rest
• Unexplained hair loss or significant changes in nail quality
• Numbness, tingling, or pins and needles in your hands or feet
• Frequent infections or illness that keeps returning
• Bone or muscle pain without obvious cause
• Heavy periods combined with persistent tiredness
• Mood changes, difficulty concentrating, or memory problems

A simple blood test can check your levels of vitamin D, iron (ferritin), B12, and folate. Your GP can then recommend targeted treatment — whether dietary changes, supplements, or further investigation.

How Tracking Your Diet Helps Prevent Deficiencies

The best approach to vitamin deficiency is prevention — spotting gaps before symptoms develop. Here is how food tracking can help:

See your actual intake vs recommended levels

A food tracking app that shows micronutrient data lets you compare your real daily intake against UK Nutrient Reference Values. If you consistently hit only 50% of your iron target, for example, you know to take action before fatigue sets in.

Identify patterns over time

A single day does not tell you much, but tracking for a week reveals clear patterns. You might discover that your B12 intake is fine on weekdays (when you eat eggs for breakfast) but drops on weekends. Or that your vitamin D-rich food intake is almost nonexistent outside of summer.

Make targeted improvements

Rather than taking a blanket multivitamin, tracking helps you identify exactly which nutrients need attention. Perhaps you only need to add a handful of pumpkin seeds for zinc, or switch to fortified plant milk for B12. Small, targeted changes are more effective and sustainable.

NutraSafe tracks over 20 vitamins and minerals with every meal you log. Scan barcodes, see your daily micronutrient breakdown, and understand exactly where your nutrition stands — before your body has to send you warning signs.

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