Supplements: What Do We Really Need?

Before looking at individual supplements, it is worth remembering where most nutrients should ideally come from: food.

A varied diet based largely on whole and minimally processed foods can provide an enormous range of vitamins, minerals, essential fats, amino acids, antioxidants and other compounds that work together in ways that we do not yet fully understand.

Supplements can have an important role, however they should generally supplement a healthy diet rather than compensate for a poor one.

There are also situations where obtaining enough of a particular nutrient from food alone can be difficult. Individual needs vary according to age, diet, lifestyle, medical conditions, medications, geographical location and many other factors.

This is where supplementation can become useful.

One of the most sensible questions to ask before taking a supplement is whether you actually need it.

Sometimes the answer can be established through a blood test. Vitamin D, vitamin B12, iron status and several other nutrients can be assessed using established laboratory markers, although even these results need to be interpreted in context.

A normal result does not necessarily mean that every aspect of nutritional status is perfect, and a result outside a reference range does not automatically mean that taking a supplement is the right response. Diet, symptoms, lifestyle, medication and individual circumstances all matter.

There are also complementary approaches to assessing nutritional needs. Applied Kinesiology, for example, is used by some practitioners as part of a broader assessment of nutritional status and individual requirements. It takes a different approach from conventional laboratory testing and can form part of a wider practitioner-led assessment alongside diet, lifestyle and symptoms.

Perhaps the most useful approach is not to rely on any single piece of information. Where appropriate, laboratory testing can provide objective measurements, while a good practitioner can consider those results alongside the person as a whole.

There is another important consideration that is often overlooked: not all supplements are created equal.

The supplement industry contains some excellent manufacturers producing carefully formulated, well-tested products. It also contains companies whose products may be poorly formulated, inadequately tested, contaminated, inaccurately labelled or simply designed to capitalise on the latest health trend. It is not well regulated generally.

That makes choosing a supplement rather more important than simply finding the cheapest product or the one with the most impressive-looking label.

Look at the manufacturer. Check how transparent they are about ingredients and testing. Look at the form of the nutrient being provided and the actual dose. Where possible, look for appropriate independent quality testing or certification. You might also want to assess the quality of the capsule.

This is particularly important when a supplement has suddenly become fashionable.

Research the supplement as carefully as you research the reason for taking it.

Creatine has traditionally been associated with bodybuilders and athletes, however its role is much broader than that.

Creatine is a naturally occurring compound involved in the production of energy, particularly in muscle. We obtain some from food, especially meat and fish, and the body also produces it.

Supplementing with creatine can increase the amount of creatine stored in muscle and has strong evidence for improving strength and power when combined with resistance or high-intensity exercise.

One of the more interesting developments in recent years has been the growing interest in creatine for healthy aging. Maintaining muscle mass and strength becomes increasingly important as we get older, and resistance exercise combined with adequate nutrition is one of the most effective ways of supporting this. Creatine may provide an additional benefit, particularly when combined with resistance training.

There is also growing interest in possible cognitive benefits, although this is an area where the evidence is still developing and appears to vary between different groups.

Creatine is generally well tolerated. It can cause some initial water retention and, in some people, digestive discomfort. Concerns about kidney damage in healthy individuals taking recommended doses have not been supported by the evidence, although people with existing kidney disease should discuss supplementation with their healthcare professional.

Creatine monohydrate has been extensively studied and is one of the better-supported forms of creatine. Yet creatine is now appearing in all sorts of protein powders, pre-workout products and “muscle-building” blends, some of which contain substantial amounts of sugar, sweeteners or numerous additional ingredients that you may not actually want or need.

Sometimes the simplest product is the best product: if you want creatine, you may not need a complicated powder containing ten other ingredients. For a relatively inexpensive supplement with a substantial body of research behind it, creatine is one of the more compelling options.

Vitamin D is unusual because, unlike most vitamins, our bodies can produce it when our skin is exposed to sunlight. It plays an essential role in calcium absorption, bone health and muscle function, and contributes to normal immune function.

How much vitamin D we produce depends on several factors, including geographical location, season, skin pigmentation, age, clothing and the amount of time we spend outdoors. People who have limited sunlight exposure may be particularly susceptible to low vitamin D levels.

A blood test measuring 25-hydroxyvitamin D [25(OH)D] can help assess vitamin D status. However, one of the most interesting questions is whether the standard recommended daily intakes are actually sufficient for the population they are intended to serve.

In the UK, the recommended intake for most people aged four and over is 400 IU (10 micrograms) per day. In the United States, the recommended intake for most adults up to age 70 is 600 IU (15 micrograms) per day.

These figures are widely quoted and often accepted without question. However, a paper published in 2014 by researchers Paul Veugelers and John Paul Ekwaru challenged the statistical calculation underlying the US recommendation. Its title was A Statistical Error in the Estimation of the Recommended Dietary Allowance for Vitamin D.

The authors argued that the calculation had not correctly accounted for the variation between individuals when estimating the amount of vitamin D required to achieve a specified blood level in 97.5% of the population. Their reanalysis suggested that approximately 8,895 IU per day might be needed to achieve a blood vitamin D level of at least 50 nmol/L in 97.5% of people.

The difference is extraordinary. Compared with the UK recommendation of 400 IU, the figure proposed by the paper is more than 22 times higher. Compared with the US recommendation of 600 IU, it is nearly 15 times higher.

This was not simply an argument that the authorities had chosen a cautious intake. The researchers challenged the statistical calculation used to establish the recommendation in the first place. If an average response does not adequately represent the variation between individuals, the resulting recommendation may underestimate the intake needed to achieve the intended blood level across most of the population.

The paper's estimate should nevertheless be interpreted carefully. It was extrapolated beyond the supplementation doses examined in the original data, and it has not become an accepted universal recommendation. Furthermore, the UK recommendation has a different basis: it was designed to help maintain a blood level of at least 25 nmol/L to protect musculoskeletal health when sunlight exposure is minimal, whereas the paper's calculation used a target of 50 nmol/L. The two figures therefore do not measure precisely the same thing.

Even so, the scale of the discrepancy raises an important question. The paper was published in 2014, yet the standard recommendations have not been adjusted in line with its estimate. Subsequent scientific discussion has not produced a universally accepted replacement figure, and the optimal vitamin D level for every health outcome remains uncertain.

The lesson is not that everyone should take 8,895 IU of vitamin D daily. It is that official recommendations are not infallible, and that the standard recommended intake should not automatically be regarded as the optimal amount for every individual or every health goal.

A higher intake may be appropriate for some people, depending on their circumstances and vitamin D status. However, more is not automatically better. Vitamin D is fat-soluble, and excessive supplementation can cause dangerously high calcium levels, potentially damaging the kidneys and other organs. The US adult upper intake level for routine daily consumption is 4,000 IU, although clinicians may use higher doses for specific indications with appropriate supervision.

The sensible approach is to consider individual circumstances, testing where appropriate, and whether supplementation is achieving its intended purpose. Rather than relying solely on a standard figure, it is worth asking whether vitamin D status is adequate and what, if anything, needs to be done to improve it.

Fish oils are among the most widely used supplements, largely because omega-3 fatty acids have an impressive reputation for supporting cardiovascular and overall health.

The two long-chain omega-3 fatty acids most commonly discussed are EPA and DHA. Oily fish such as sardines, mackerel, salmon and anchovies are particularly good dietary sources.

There is good reason to include oily fish in a healthy diet. The picture becomes more complicated when we move from eating fish to taking fish-oil capsules.

Research has found benefits in certain populations and for particular outcomes, while evidence for routine supplementation of everyone is considerably less clear. Dose also matters, and very high doses should not simply be assumed to be better.

For many people, the first question might therefore be: How much oily fish am I eating?

If dietary intake is low, supplementation may be worth considering, particularly where there is a specific reason for it. However, it is important to look at the actual amounts of EPA and DHA in a product rather than simply choosing one labelled 'fish oil'.

The quality and freshness of fish oil matter too, making reputable sourcing and appropriate quality control particularly important.

Coenzyme Q10, or CoQ10, is a naturally occurring compound found throughout the body. It plays an important role in mitochondrial energy production, which makes it particularly interesting when we consider energy metabolism and aging.

CoQ10 production tends to decline with age, and interest in supplementation has grown considerably. Because mitochondria are responsible for producing much of the energy our cells require, CoQ10 has attracted interest in areas ranging from energy and physical performance to cardiovascular health and healthy aging.

There is some encouraging research into its potential benefits, although the strength of the evidence varies considerably depending on the particular health outcome being investigated. CoQ10 can also interact with certain medicines, including warfarin, so anyone taking prescribed medication should check with an appropriate healthcare professional before starting it.

This is another example of where a plausible biological mechanism does not automatically translate into a proven clinical benefit. CoQ10 is interesting, and it may have a useful role for some people, but we should be cautious about turning promising research into universal claims.

Magnesium is involved in hundreds of biochemical reactions throughout the body, including those relating to energy production, muscle and nerve function, blood glucose regulation and protein synthesis. It is found in foods such as nuts, seeds, whole grains, legumes and leafy green vegetables.

Magnesium supplements are extremely popular, particularly for sleep, stress, muscle cramps and relaxation. Some of these uses have reasonable evidence behind them, while others are less certain.

One complication is that assessing magnesium status is not always straightforward. Most of the body's magnesium is stored in bones and tissues rather than circulating in the blood, so a standard serum magnesium measurement does not necessarily provide a complete picture.

That raises an important practical question: if it is difficult to establish a deficiency with certainty, how do we know whether supplementation is helping?

This is where looking at the individual response becomes useful. If someone has a particular symptom or problem that prompted them to try magnesium, has that problem improved? Do they feel noticeably better? Has a measurable marker changed? Has a practitioner identified a reason to continue?

In some circumstances, it may also be appropriate to repeat testing after a period of supplementation, particularly where there is an established deficiency that can be measured reliably. The aim should not simply be to take a supplement indefinitely, but to establish whether it is doing what we hoped it would do.

High supplemental doses can cause diarrhoea, and people with impaired kidney function need particular caution because magnesium can accumulate in the body. Rather than assuming that everyone needs a magnesium supplement, it makes sense to review dietary intake and consider whether there is a credible reason to supplement.

The world of supplementation becomes particularly fascinating when we look at healthy aging and longevity.

David Sinclair, the Harvard geneticist and aging researcher, is a good example. He has publicly discussed taking a specific combination of supplements and other compounds as part of his own longevity approach, including NMN, resveratrol, vitamin D and several others.

Some of the compounds he discusses have interesting biological mechanisms and early human research behind them. However, others remain experimental, and there is currently no robust evidence that taking a particular “longevity stack” will extend human lifespan.

This is an important distinction. A respected scientist taking a supplement is not evidence that the supplement works. It is, however, a good illustration of how rapidly the field of longevity and nutritional science is developing – and how important it is to distinguish established benefits from promising hypotheses.

It is also worth remembering that supplements are only one part of the picture. Diet, physical activity, muscle strength, sleep, stress, social connection and other lifestyle factors all contribute to health as we age. These foundations should not be overlooked in pursuit of the latest compound associated with longevity.

This is perhaps one of the most overlooked questions about supplementation but is also one of the simplest.

An often-neglected part of supplement use is assessing the outcome. It is easy to start taking a product and continue indefinitely without knowing whether it is helping, especially if you are taking more than one.

Before starting a supplement, consider why you are taking it and what you hope to achieve. Is it intended to correct a confirmed deficiency, address a dietary gap, support a specific health goal or simply explore a potential benefit?

Where there is a reliable blood marker, might it be worth testing again after an appropriate period to see whether the supplement has actually changed your nutritional status?

Of course, not every benefit can be measured by a blood test, and not every supplement should be expected to produce a noticeable sensation. Some nutrients are important precisely because they prevent problems rather than create an obvious feeling of wellbeing.

Nevertheless, having a reason for taking a supplement and periodically asking whether that reason still exists is a sensible approach. A deficiency may have been corrected, dietary habits may have improved, or the original reason for taking a product may no longer apply.

Taking more supplements is not necessarily a sign of taking better care of ourselves. Sometimes the most useful decision is to stop taking something that is unnecessary.

Supplements can play a valuable role in supporting health, particularly when they address a genuine nutritional need. Creatine has strong evidence for improving certain aspects of exercise performance, while vitamin D, omega-3 fatty acids, CoQ10 and magnesium each have important biological roles and may be useful in particular circumstances.

However, the evidence is not equally strong for every product or every claimed benefit. A nutrient being essential does not automatically mean that taking extra amounts will improve health, and a promising finding does not necessarily translate into a meaningful long-term benefit for everyone. For some people, supplementation may be an important part of maintaining good health. For others, it may provide little additional benefit beyond an already nutritious diet.

The strongest case for taking a particular supplement is often where there is a demonstrated deficiency, a known increased requirement or good evidence that a particular supplement provides a meaningful benefit for a particular group.

Supplements can support good health. They cannot replace the foundations of it. If you do decide that a supplement may be appropriate, do your research. Look at the evidence for the particular supplement, understand why you are taking it, check the dose and choose a reputable, quality-controlled product.

Recommended daily intakes are useful starting points, but they are not infallible measures of individual need. The debate around vitamin D illustrates why it is worth examining the evidence behind recommendations rather than accepting every figure uncritically. Equally, questioning an official recommendation does not mean that a substantially higher dose is automatically safe or beneficial.

Perhaps the best approach is to begin with a good diet, regular exercise, good sleep, lowered stress and spending time outdoors. Consider individual circumstances, choose quality products where supplementation is justified and review whether they are achieving their intended purpose.

Ultimately, the aim is not to take the greatest number of supplements, or to follow the latest trend. Supplementation should be one part of a bigger picture. As with so many things, it is best to make informed decisions that support health, resilience and wellbeing over the long term.

If you have been taking a supplement or supplements, where possible, ask yourself the simplest question of all:

Is it/are they actually helping me?

Because when it comes to supplements, more is not necessarily better – and better informed is almost always better.