Which supplements are really good for us?

Jenna Farmer
By Jenna Farmer,
updated on Aug 2, 2021

Which supplements are really good for us?

From glossier hair to shedding weight and boosting your energy, we’re often told that supplements could be the key to our health goals. But which ones are worth taking, and which ones offer false promises? Jenna Farmer helps separate fact from fiction when it comes to all things vitamins

With so many vitamin supplements on the market, it can be tough to figure out which ones might actually be worth investigating. While a healthy balanced diet can actually go a long way to meeting your nutritional needs, supplementing key vitamins may be beneficial to ensure you’re not deficient in any important areas, and to help with your general wellbeing.

As nutritionist Sonal Shah explains: “The most common nutritional deficiencies are vitamin D, magnesium, calcium, iron, zinc and selenium.” So, with that in mind, let’s take a closer look at the vitamin supplements worth considering...

Vitamin D

It’s a common deficiency in the UK, with one in five people thought to be low in vitamin D, which can result in fatigue, joint pain, and low moods. The good news is that in the summer months, most of us get plenty of vitamin D from the improved weather. However, over winter when sunlight is lacking, we’re much more likely to be low in vitamin D.

“It’s important to take a good, absorbable form of vitamin D throughout autumn and winter,” explains nutritionist Sonal. The NHS currently recommends that all adults (and children above one) supplement with 10 micrograms a day of vitamin D from October through to March – and this includes those who are pregnant or breastfeeding. Studies have found supplementing vitamin D has many health benefits, including potentially improving symptoms of IBS, as found in a study published in the International Journal of Preventive Medicine.

But what about the rest of the year? “In the summer months, as long as there is moderate exposure of the sun on the body areas without sun protection factor, it’s fine to take a break from vitamin D supplements, if your levels are within the healthy range, or to take a lower dose,” adds Sonal.

However, if you still spend a lot of time inside during summer, or are still suffering with the symptoms of a vitamin D deficiency, then it’s worth getting your levels tested and potentially supplementing all year round – but best to speak to a professional to check there’s nothing else needed to support your health if this is the case.



Iron deficiency anaemia can be recognised by symptoms such as fatigue and breathlessness, and is particularly common in women of a childbearing age, but can also occur in men and postnatal menopausal women. In fact, it’s thought that a quarter of women in the UK have low iron stores.

The causes of anaemia can really vary, but include things such as pregnancy, heavy periods, restricted diets, or could be a sign of gastrointestinal conditions such as coeliac disease and inflammatory bowel disease. Because of the range of causes, it’s really important to speak to your doctor before using iron supplements, as they can do a blood test to check your levels, and potentially do further investigations to discover the cause for you.

Studies, including one in the British Medical Journal Open, have shown iron supplementation can help with fatigue levels, and since some people find that their iron levels dip during pregnancy, or when they are on their period, it might be a case of only needing to supplement at certain times – and again, it’s important to speak to a doctor to discuss this first.

One thing to be aware of is some people report that regular iron supplements can sometimes cause tummy issues, but there are lots of variations to persevere with if you need an extra iron boost – including liquid supplements that may be gentler on your digestion, while injections and infusions are an option for those who are severely anaemic.

Vitamin B12

This is far less common than iron deficiency, and your need to supplement depends on a few factors. Firstly, your risk increases with age: 6% of people under 60 are deficient, but this jumps to 20% for over 60s, according to the NICE website. In turn, take a look at your diet; around 11% of vegans are deficient in B12, as it can be hard to source this without eating meat and eggs.

Symptoms of this deficiency can include tingling in your hands and feet, mouth ulcers, depression, and fatigue, so if you suspect you have low Vitamin B12, it’s important to get tested promptly as if untreated it can cause nerve damage.

Furthermore, while there isn’t concrete evidence that a lack vitamin B12 is associated with an increased risk of depression, an overview of studies in the journal Cureus does appear to show that supplementation by those with or prone to depression could have positive effects. Therefore while supplementation could help, it’s vital to ensure you seek appropriate medical support for your mental wellbeing as a whole.

"It’s important to look beyond the marketing promises and consider your own body’s nutritional needs"


“For optimum health and nutrition it’s ideal to consider supplementing magnesium for more than 300 roles in our body – including helping with bones, muscles, mood and energy,” explains Sonal Shah.

Magnesium is often found in plentiful supply in our diet, in foods such as spinach, nuts, and wholegrains. However, those in certain risk categories – such as those with type 2 diabetes, gastrointestinal conditions, those who are pregnant, or on certain medications (such as proton pump inhibitors and antibiotics) – might consider getting their levels tested to see if they need to supplement. Anecdotally, magnesium is often suggested to help muscle cramps, but there’s not much scientific evidence to prove it works. However, other studies have shown magnesium is effective at improving sleep issues such as insomnia, so it may generally help to relax you.

There’s no doubt supplements can be a bit of a minefield, so it’s important to look beyond the marketing promises and consider your own body’s nutritional needs. Whether that’s looking at your own diet and finding gaps, or having a chat to your GP about being tested for deficiencies, understanding the supplements your body requires in conjunction with a good diet is key for your overall wellbeing.

The supplements you need to ditch

Hair gummies: Many influencers promise glossy locks are within our reach if we just buy hair gummies – but do they really work? Many of these just contain the vitamins you could find in a cheaper multivitamin. It’s far better to just take what individual supplements your body actually needs.

Fat burning pills: As well as encouraging an unhealthy relationship with your body, fat burning pills often have no scientific backing, and may cause unpleasant side-effects.

“The composition of what is in these formulas is what matters – things like green tea and conjugated linoleic acid (CLA) have some evidence to support the metabolism – but the rest are just clever marketing, and not enough quality ingredients to support their weight loss claims,” adds Sonal Shah. A cup of green tea a day can’t hurt, but there’s no need to buy ‘fat burning pills’ to get this.

Detox supplements: Diet teas and detox plans promise to help us ‘cleanse’ our body, but don’t live up to the hype. Many contain a blend of herbs, such as senna, that are designed to induce a laxative effect. In fact, a study published in the Journal of Dietary Supplements investigated this, by assigning healthy females a detox herbal supplement with ingredients such as senna and slippery elm bark, and found it provided no beneficial effects at all for both their body composition or gastrointestinal symptoms.

Sonal Shah is a nutritional therapist, health tutor, and director of Synergy Nutrition. Find out more about supplements, and get in touch with Sonal on

Jenna Farmer

By Jenna Farmer

Jenna Farmer is a freelance health writer and nutritional therapist. She has Crohn’s disease and blogs about her journey to improve gut health.

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