magnesium

By Helen Chow, ND, Dip Herb, UK-qualified Naturopath & Herbalist
Nutrition-Food Coach, Designer Realities Mind Coach
Article Published on 22 December 2020. Reviewed & Updated on 2 October 2026 

You can eat what looks like a perfectly respectable diet and still quietly miss something your body needs.

That becomes easier after 50—not because your body has suddenly become incapable, but because life and physiology have changed. You may eat less than you once did. Your appetite may be smaller. You may avoid certain foods because they upset your digestion. A medicine may alter absorption.

Menopause changes the conversation around bone and muscle. And a diet that is wonderfully “clean” can still be short of vitamin B12, iron, zinc or magnesium if it has become too narrow.

This is where women are sometimes sold a cupboard full of supplements.

I would rather help you ask a better question: what might you actually need, and how can you find out?

The quick answer

Women over 50 should pay particular attention to vitamin D, calcium, vitamin B12, iron, zinc and magnesium. Food should usually provide the foundation, but age, menopause, sun exposure, dietary restrictions, digestive conditions and medicines can alter your needs or absorption.

More is not automatically better. A blood test, medication review or individual assessment is often more useful than guessing—especially for vitamin D, B12 and iron. 

In this article

• Why micronutrients become easier to overlook after 50
• Vitamin D
• Calcium
• Vitamin B12
• Iron
• Zinc
• Magnesium
• Food-first ways to cover more bases
• Medicines and absorption
• When testing or supplements make sense
• A simple seven-day micronutrient check
• Frequently asked questions

Micronutrients are small—but their jobs are not

Protein, carbohydrate and fat are called macronutrients because we need them in relatively large amounts. Vitamins and minerals are micronutrients because the amounts are smaller.

Small does not mean unimportant.

They help you make red blood cells, release energy from food, maintain nerves, contract and relax muscle, support immune function and keep bone tissue renewing itself. They work as a team. That is why I am wary of treating one fashionable vitamin as though it runs the entire body single-handedly.

Your overall meal pattern still comes first. If you would like the wider framework, begin with what a nourishing meal can look like after 50. Then use this article as your closer inspection.

Why your nutrient picture may change after 50

Several things can alter the balance:

• You may need fewer calories while still needing plenty of nutrients.
• Menopause increases the importance of protecting bone and muscle.
• Skin makes less vitamin D with age, and indoor living or covering the skin reduces sun exposure.
• Stomach acid can decline, and certain medicines can further affect vitamin B12, iron or magnesium absorption.
• Digestive conditions, bariatric surgery or long-term diarrhoea can reduce absorption.
• A vegetarian or vegan diet changes the planning needed for B12, iron and zinc.
• Removing dairy, eggs, grains, legumes, nuts or other food groups for genuine tolerance reasons can create gaps unless you replace what those foods provided.
• Eating very little while trying to lose fat makes it harder to obtain enough of almost everything.

This is one reason I prefer adequate nourishment to heroic restriction. A smaller body still needs raw materials.

Vitamin D: The sunlight nutrient that often needs a closer look

Vitamin D helps the body absorb calcium and has roles in muscle and immune function. Unlike most nutrients, food is not usually our main source. Sunlight on the skin contributes substantially, although season, latitude, skin pigmentation, clothing, sunscreen use, age and time spent indoors all affect production.

Food sources include oily fish, egg yolks and fortified foods. In British food traditions that might mean eggs or mackerel; in Japanese or Malaysian cooking, salmon, sardines or other oily fish may be more familiar. But food alone does not always close the gap.

In the UK, government advice recommends considering a daily 10 microgram vitamin D supplement during autumn and winter. Some people with little sun exposure or darker skin are advised to consider it throughout the year. Other countries have different guidance, so your location matters.

When a vitamin D test may help

A clinician may consider a 25-hydroxyvitamin D blood test when deficiency is suspected—for example, with bone pain, muscle weakness, osteoporosis, malabsorption or other relevant risk factors. Routine testing of everyone is not universally recommended.

Please do not assume that a very high dose is “extra healthy”. Vitamin D is fat-soluble and excessive supplemental intake can raise calcium in the blood, contributing to nausea, weakness, kidney stones and, in severe cases, kidney or heart problems.

Calcium: important, but never a solo act

Calcium is best known for bone, but it is also involved in muscle contraction, nerve signalling and blood clotting. After menopause, bone loss can accelerate as oestrogen falls.

That does not mean every woman needs a large calcium tablet. First look at food and at the whole bone-health picture: vitamin D, protein, resistance exercise, hormones, smoking, alcohol and relevant medicines all matter. I explain that network more fully in my article on bone structure.

Useful calcium foods include:

• milk, yoghurt and cheese;
• sardines or salmon with edible bones;
• calcium-set tofu;
• fortified unsweetened plant drinks;
• some leafy greens, including kale and pak choi;
• and smaller contributions from many other foods.

Absorption varies. Calcium in dairy and fortified drinks is generally well absorbed. Spinach contains calcium, but its oxalate also makes much of that calcium unavailable. And if dairy, soy or high-oxalate greens do not suit you, that does not make you “difficult”; it simply means we plan differently.

Large calcium doses are not automatically superior. If a supplement is appropriate, dose, timing, total food intake, kidney history and medicine interactions deserve attention. Calcium can interfere with the absorption of levothyroxine and some antibiotics when taken too close together, so ask your pharmacist about spacing.

Vitamin B12: Energy is only part of the story

Vitamin B12 is needed for red blood cell formation, DNA synthesis and healthy nerves. Low B12 can show up as tiredness, weakness, a sore tongue, pins and needles, numbness, poor balance, memory changes or anaemia. Nerve symptoms can sometimes occur without obvious anaemia.

Natural food sources are mainly animal foods: meat, liver, fish, shellfish, eggs and dairy. Fortified foods and supplements are essential planning tools for vegans, because unfortified plant foods do not provide reliable B12.

Your body needs stomach acid and a protein called intrinsic factor to absorb food-bound B12 efficiently. With age, atrophic gastritis becomes more common. Long-term use of acid-suppressing medicines can reduce absorption from food, and metformin can lower B12 status in some people.

If you take metformin, a proton-pump inhibitor, have had stomach or bowel surgery, live with coeliac or Crohn’s disease, eat a vegan diet, or have unexplained neurological symptoms, ask whether B12 assessment is appropriate. A serum B12 result may sometimes need interpretation alongside symptoms and other markers rather than being treated as a perfect yes-or-no answer.

And no, a B12 supplement does not act as a general energy stimulant when you already have enough. Correcting a deficiency is very different from pushing a normal level higher.

Iron: Don’t guess—especially after menopause

Iron helps make haemoglobin, which carries oxygen in red blood cells, and myoglobin, which supplies oxygen to muscle. Too little can leave you tired, breathless, weak, cold, headachy or unable to concentrate.

Before menopause, menstrual blood loss is a common reason for low iron. After menopause, iron requirements generally fall. New iron-deficiency anaemia then deserves proper investigation rather than a casual bottle of iron, because blood loss or a digestive problem may need to be ruled out.

Food iron comes in two broad forms:

• Haem iron, from meat, liver, poultry, fish and shellfish, is generally absorbed more readily.
• Non-haem iron, from beans, lentils, tofu, seeds, leafy greens and fortified foods, is more affected by the rest of the meal.

Vitamin C-rich food can improve absorption of non-haem iron. Tea and coffee taken with an iron-rich meal can reduce it. You do not have to abandon your tea; simply move it away from the meal if iron deficiency is an issue.

Traditional food cultures offer many options: beef and liver in European cooking, oysters and mussels in coastal cuisines, dhal with a vitamin C-rich vegetable, or tofu with pak choi and peppers. The useful choice is the one you tolerate and will actually eat.

Ask for assessment rather than self-treating persistent fatigue. A full blood count and ferritin are common starting points, but ferritin can rise during inflammation, so the result needs context. Too much iron can be harmful, cause digestive upset and mask the real reason for anaemia.

Zinc: Quietly involved in repair, taste and immunity

Zinc supports hundreds of enzyme reactions, including those involved in immune function, wound healing, DNA synthesis and the senses of taste and smell.

Rich sources include oysters, red meat and other shellfish. Poultry, dairy and eggs contribute smaller amounts. Beans, lentils, nuts, seeds and whole grains contain zinc too, although phytates in plant foods reduce its absorption. Soaking, sprouting, fermenting and leavening can reduce phytate—but only use those foods or methods if they suit your digestion.

Women who eat little animal food, have chronic diarrhoea, inflammatory bowel disease, bariatric surgery or a very restricted diet may need closer attention to zinc.

High-dose zinc is not a harmless immune “boost”. Taken for long periods it can interfere with copper absorption, cause anaemia and neurological problems, and affect some medicines. More is not better; balance is better.

Magnesium: Important, popular—and often oversold

Magnesium participates in hundreds of reactions involving energy production, nerve function, muscle contraction, blood glucose regulation and blood pressure. It is present in leafy greens, beans, nuts, seeds, whole grains, dairy, fish and some mineral waters.

That list can be awkward if you do not tolerate legumes, nuts, grains or high-fibre greens. You may need to look more deliberately at tolerated choices—perhaps fish, yoghurt, pumpkin seeds if suitable, cooked greens, avocado or a magnesium-rich mineral water—rather than forcing down foods that cause pain or bloating.

Magnesium supplements are widely promoted for sleep, cramps and stress. Some women find particular forms helpful, but symptoms alone do not prove magnesium deficiency. Cramps, fatigue and poor sleep have many possible causes.

Supplemental magnesium commonly causes diarrhoea, and impaired kidney function increases the risk of dangerous accumulation. Magnesium can also interfere with the absorption of some antibiotics and osteoporosis medicines, so timing matters.

Six nutrients, one real plate

You don’t need six separate “superfoods”. A varied meal can cover several jobs at once.

Notice how these are recognisable foods, not powders pretending to be lunch.

This is also why returning to more real food can improve nutrient density without turning eating into a mathematical exercise. Ultra-processed foods may be fortified, but they can still displace protein-rich and naturally nutrient-dense meals.

Foods first doesn’t mean “supplements never”

“Food first” is a useful principle, not a moral rule.

A supplement may be entirely sensible when:

• government guidance recommends it, as with vitamin D in particular circumstances;
• a blood test identifies a deficiency;
• absorption is impaired;
• food allergies or dietary choices make a nutrient difficult to obtain;
• a clinician prescribes a therapeutic dose;
• or a life stage creates a specific need.

But the bottle should have a job. It should not be there because an influencer made deficiency sound inevitable.

Before buying, ask:

1. What problem am I trying to solve?
2. Is there evidence that I am low or at particular risk?
3. What dose is appropriate, and for how long?
4. Could this interact with my medicines or another supplement?
5. When will I review whether I still need it?

Medicines can change the nutrient conversation

This is not a complete interaction list, but it shows why your pharmacist is worth including:

Do not stop prescribed medicine because of an article—or because a supplement label frightened you. Ask the prescriber or pharmacist to review the combination.

Which nutrients might warrant testing?

Not every nutrient has a simple, perfect blood test. Testing should be guided by symptoms, risk factors and clinical judgement.

• Vitamin D: 25-hydroxyvitamin D is the usual status test when indicated.
  
• Vitamin B12: serum B12 is commonly used; borderline or conflicting cases may need additional markers and clinical interpretation.
  
• Iron: a full blood count and ferritin are common starting points, sometimes with other iron studies. Inflammation can complicate ferritin interpretation.
  
• Magnesium: serum magnesium can detect significant abnormalities but does not perfectly reflect total body stores.
  
• Zinc: testing can be useful in selected situations, but levels vary with meals, time of day and inflammation.
  
• Calcium: blood calcium is tightly controlled and does not tell you whether your diet is adequate or your bones are strong. Bone-density assessment answers a different question.
  

You should seek proper health assessment if you experience the following:

• Persistent fatigue
• Persistent and/or unexplained breathlessness
• Numbness
• Balance changes
• Unexplained weakness
• Bone pain
• Unintended weight loss 
• A major change in appetite 

Please do not reduce every symptom to a vitamin.

Your seven-day micronutrient check

For one week, do not change anything. Simply notice.

At the end of each day, ask:

• Did I eat a meaningful protein source at two or three meals?
• Did I include fish, eggs, meat, dairy or a properly planned plant alternative?
• If I avoid animal foods, where did today’s reliable B12 come from?
• Did I eat any calcium-rich food?
• Did I include an iron- and zinc-rich food?
• Did I include magnesium-rich foods that I genuinely tolerate?
• Have I relied on snack foods or supplements while real meals slipped away?

Then look across the whole week, not one “perfect” day. If your diet has become restricted, start by widening it safely. If fat loss is your goal, remember that your body still needs enough protein and micronutrients; my guide to protein after 50 explains why protecting muscle matters.

And if your energy or weight is changing in a way that does not make sense, look beyond a single nutrient. Blood sugar regulation, thyroid health, sleep, inflammation and total food intake may all be part of the picture. The starting guide to metabolic health after 50 can help you see that wider landscape.

From the Gourmet Sifu Kitchen

Health Sifu tells you why. Gourmet Sifu shows you how to make it delicious.

Knowing that sardines contain calcium or that oysters are rich in zinc is one thing. Knowing how to turn those ingredients into food you genuinely look forward to eating is another.

That is where Gourmet Sifu comes in.

For another example of how a nutrient can be translated into familiar foods, have a look at Gourmet Sifu’s guide to vitamin E foods. Vitamin E is not one of the six nutrients we have explored in detail here, but the same food-first principle applies: begin with what the nutrient does, then discover enjoyable ways to put it on your plate.

Here are three delicious ways you could put these nutrient-rich ingredients to work:

• Ten-minute sardines with lemon, herbs and warm vegetables
• Malaysian-style calcium-set tofu with pak choi and ginger
• Gentle beef-and-pumpkin mineral-rich stew

These are exactly the kinds of practical dishes I shall be developing on Gourmet Sifu. Health Sifu can explain the nutritional reason; Gourmet Sifu can give you the ingredients, quantities, substitutions and cooking method.

Frequently Asked Questions

Should every woman over 50 take a multivitamin?

No. A multivitamin can provide useful insurance in some circumstances, but it cannot correct an unsuitable dose, diagnose a deficiency or replace nourishing meals. Products also vary enormously. Choose according to an identified need, not the longest ingredient list.

Is it safe to take vitamin D, calcium and magnesium together?

They can sometimes be used together, but the right dose depends on food intake, blood results, kidney function, medical history and medicines. Large mineral doses may compete with medicines or cause digestive effects. Ask a pharmacist to check timing.

Why am I tired if my iron is normal?

Fatigue can be related to B12 or folate deficiency, thyroid problems, sleep, infection, inflammation, blood glucose changes, low calorie or protein intake, medication effects and many other causes. “Normal iron” also needs definition: haemoglobin, ferritin and other markers tell different parts of the story.

Can I get enough nutrients on a vegetarian or vegan diet after 50?

Yes, with thoughtful planning. Vitamin B12 needs a reliable fortified source or supplement on a vegan diet. Protein, iron, zinc, calcium, vitamin D and sometimes iodine or omega-3 fats also deserve deliberate attention. 

My guide to vegetarian protein after 50 explores these choices in greater depth.

Are food-based supplements automatically safer?

No. A natural origin does not guarantee an appropriate dose, purity, absorption or freedom from interactions. What matters is the ingredient, amount, quality, your health and why you are taking it.

Does a blood test show every nutrient deficiency?

No. Some markers are useful; others are affected by inflammation, recent meals or tight regulation in the bloodstream. Tests must be interpreted alongside symptoms, diet, medicines and medical history.

A Health Sifu Note

Your body does not need nutritional perfection. It needs enough raw material, often enough, in forms you can digest and enjoy.

Please do not let a list like this frighten you into six new bottles. Let it help you look at your meals with kinder, more intelligent eyes. Perhaps you need more oily fish. Perhaps your restricted diet needs a carefully chosen replacement. Perhaps persistent tiredness deserves a blood test rather than another coffee.

The aim is not to chase nutrients one by one. It is to build a well-nourished woman.

Health Sifu
Make Smarter Choices
Consciously. Deliberately.

Scientific References & Further Reading

1. Vitamin D — Fact Sheet for Consumers — US National Institutes of Health, Office of Dietary Supplements. A clear overview of vitamin D sources, deficiency, health roles, upper limits and the risks of excessive supplementation.
2. Vitamin D — NHS. A practical explanation of the UK’s seasonal supplement advice and the groups advised to consider vitamin D throughout the year.
3. Calcium — Fact Sheet for Consumers — US National Institutes of Health, Office of Dietary Supplements. Useful food-source tables plus balanced information on absorption, recommended intake and supplement safety.
4. Vitamin B12 — Fact Sheet for Health Professionals — US National Institutes of Health, Office of Dietary Supplements. A detailed, well-referenced guide to absorption, food sources, older age, vegan diets and medicine considerations.
5. Metformin and reduced vitamin B12 levels: new advice for monitoring patients at risk — UK Medicines and Healthcare products Regulatory Agency. Explains that reduced B12 is a common metformin effect and advises testing when deficiency is suspected and considering periodic monitoring in people with risk factors.
6. Iron — Fact Sheet for Consumers — US National Institutes of Health, Office of Dietary Supplements. A friendly explanation of haem and non-haem iron, food sources, deficiency and the risks of unnecessary high intake.
7. Iron Deficiency Anaemia — NICE Clinical Knowledge Summaries. Clinically useful guidance on assessment and the importance of considering the cause of iron deficiency rather than simply replacing iron.
8. Zinc — Fact Sheet for Consumers — US National Institutes of Health, Office of Dietary Supplements. Covers zinc’s roles, food sources, groups at risk and why prolonged high doses can cause copper deficiency.
9. Magnesium — Fact Sheet for Consumers — US National Institutes of Health, Office of Dietary Supplements. A readable guide to food sources, deficiency risk, supplement side effects and medicine interactions.
10. Healthy Eating as You Age: Know Your Food Groups — US National Institute on Aging. An accessible “yummy” resource showing how varied real foods can support good nutrition as appetite and calorie needs change with age.

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