Supplements – Do we need them?

I am a registered nutritional therapist, and the followings are typical conversations between my clients and me:

“I eat a healthy, balanced diet. Do I still need supplements? “My nan never took any supplements and was fit as a fiddle. Why should I take them?” “Are supplements safe?” “Can I take them long-term?” “Can I overdose on supplements; they are only natural?”

You may think and ask the same questions, making you decide whether to take them or not.

Understandably, you are worried about your health and, at the same time, about your bank account. No one wants to throw money down the drain or cause harm to their health.

On the other hand, I get the opposite type of clients who love taking dietary supplements! Sometimes after a lengthy consultation, I found out they are on ten different kinds of supplements. When I ask why they take them, the answer is, “I heard or read they are good for my health”.

Now we need to draw a line between taking necessary and unnecessary supplements. Taking too many supplements in the hope of giving us good health we do more harm than good, believe me. Let’s find the middle road and shed some light on the confusing world of supplements!

Do I need supplements?

Let me emphasise my firm belief that food should always be the number one source of our macro and micronutrients. Always aim to have a reasonably good diet whenever possible. However, there are many factors (individual or environmental) when we need to rely on supplements. So, the saying that our grandparents didn’t need supplements can be true. Unfortunately, times are changing, and our lifestyle and environment are not the same as it was back in their time. There are many factors when we need to rely on dietary supplements to fill the nutritional gaps.  Let’s take a closer look at those factors:



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Individual needs

1. Borderline/low-end blood test result

When you take a blood test for vitamins and minerals, and it comes back “normal”, no further action is needed. Let me highlight that NORMAL doesn’t mean OPTIMAL. I often discuss this with my clients to aim for optimal ranges rather than normal ones. Your lower end on the scale is considered normal as it is still within the range, right?

Let me explain it with an example. Your ferritin (iron store) is, let’s say, 18. The ranges for ferritin for women are usually between 10-150 μg/L. You are ok, as it is still within the range. You would be told your levels are low if it were eight units less.  The ranges vary with blood laboratories. Some have a range between 24-200 μg/L. With them, your ferritin with the level of 18 would be classed as low.  

So, you have the symptoms of certain deficiencies (tiredness, leg cramp, hair shedding, menstrual irregularities etc.); HOWEVER, you weren’t advised to take supplements as your levels were within the “normal range”. (your ranges might be normal but not optimal)

This can be one of the reasons why you feel better and why your symptoms improve while taking certain supplements, even though your blood test shows “normal” levels.

It is worth asking for a copy of your blood work from your doctor to take a look.  It is essential to think holistically and look at the whole picture. (your symptoms and your actual blood levels)

2. Poor diet, poor appetite, following a trendy strict diet

First of all, very important to address the cause. Then start working on the issues, and in the meantime, supplementation with a good quality multivitamin is advisable.

3. Pregnancy

Pregnant women`s requirements increase as the growing baby requires many nutrients. Sometimes it is impossible to get all the nutrients you and your baby need from food to carry a healthy pregnancy. Taking a multivitamin formulated for pregnancy can give the best possible start for your baby. Not to mention the extra folic acid to prevent Spina Bifida and vitamin D to prevent pre-eclampsia. (1)(2)

4. Elderly

As we get older, our digestive system changes too. Unfortunately, the capability of our bodies to break down and absorb the nutrients we need is less effective than in our youths. We produce less hydrochloric acid and digestive enzymes, essential in breaking down the food we eat and absorbing vital nutrients. The skin thins with age, and its ability to synthesise vitamin D from sunlight becomes less effective. Also, our kidneys are less able to convert vitamin D to its active form. Vitamin D deficiency can lead to osteoporosis and fractures. (3)

The chances of being on medication over 60 are higher too. Medications are very important, but we must be aware that some can cause nutrient deficiencies. Supplements can help restore this nutrient imbalance due to ageing.

5. Being on medication

As I mentioned before, some medications can affect the levels of certain nutrients in the body.
This is an important consideration when assessing nutrient status. Supplements are beneficial in this case to correct medication-induced deficiencies. Let me mention some of the most commonly prescribed medications and the nutrients they deplete:

  • Metformin (manage type 2 diabetes) – B12, folate (folic acid)
  • Omeprazole/lansoprazole (reduce the acidity of stomach content) – iron, B12, magnesium, zinc
  • Atorvastatin (to reduce high cholesterol) – Coenzyme Q10, copper, selenium, zinc
  • Losartan (treat high blood pressure) – calcium, potassium, magnesium, Coenzyme Q10, zinc. (4)

6. Health conditions such as celiac, IBD (Ulcerative Colitis, Crohn’s disease)

Due to malabsorption and maldigestion, these health conditions can cause iron, B vitamins (especially B12), vitamins A, D, K, and E, magnesium, calcium, and selenium deficiencies. (5) You need to replace these essential vitamins and minerals.

7. Stress – Physiological and psychological

Both physiological and psychological stress can cause nutrient depletion. Psychological stress: under pressure at work, issues at home, kids, going through divorce/breaking up, moving house, even as simple as sitting in traffic etc. Physiological stress is the body`s response to stressors. It happens at a cellular level. It can be an injury, extreme exercise, infection, high blood pressure, high blood sugar, temperature extremities, travel etc. Emotional/psychological stress depletes magnesium, iron, zinc and calcium and physical stress depletes niacin (B3). (6)(7) Chronic stress is one of the biggest reasons an individual needs supplements. To replenish the reserves that stress causes and also to combat stress efficiently.

8. Excess alcohol consumption

Specific vitamin deficiencies (e.g., folic acid, B1, B5, B6, and B12) related to too much alcohol and chronic alcoholism. (8)



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1. Soil depletion

How is it possible to be deficient in vital nutrients while having the perfect diet? Nutrient levels in UK soil have plummeted over the years. Unfortunately, our soil contains fewer nutrients than it used to. It’s easy to guess that your fruits and veggies will have less or none if the soil is depleted. For example, magnesium is a vital mineral, and research shows levels are declining in soil. (9) You would need to eat four carrots today to get the same amount of magnesium found in one carrot 80 years ago.  (10)  Stress depletes magnesium by activating the sympathetic nervous system. Stressful events like over-exercising, high blood sugar, or anxiety make you use magnesium at a higher rate. (11)

The more stressed you are, the more magnesium you need. (12) Unfortunately, our world is not a calm and tranquil place at the moment, so imagine eating vitamin and mineral-depleted veggies and fruits and being under stress. What is going to happen? Big chance of being deficient.

2. Pollution/chemicals/pesticides

This might surprise you why we need supplements in these cases. Environmental pollution, pesticides and herbicides used on our veggies and fruits, and chemicals in our water increase the need for supplements. Toxins create free radicals (unstable compounds), which are detrimental to our health. (13) Specially designed antioxidant supplements can help fight these free radicals. (e.g., vitamin C, E, selenium etc.)

Are supplements safe?

Supplements sometimes receive bad press, as in everything in our world, you come across good and bad. Check the label and carefully look at the ingredients. The more unnecessary ingredients they contain, the more you should avoid them. Always buy from reputable suppliers – they should have undergone rigorous quality assurance.

Can I take them long-term?

My advice is always to take a break when using supplements unless you have a health condition where you rely on specific vitamins or minerals. If your deficiencies are caused by prescribed medication, always consult your doctor or nutritional therapist before supplementing to avoid interactions. The same applies if you are on any medication; always seek advice before buying any supplements. Therapeutically I often advise clients to take supplements for three months. Then we re-evaluate the needs via symptoms and blood tests. Deficiencies usually resolve within three months of supplementation.

Can I overdose on supplements?

Yes, you can. Certain minerals like iron and fat-soluble vitamins, like vitamins A, and D, can be harmful if taken in excess. (14) (15) (16) Although overdosing on vitamin D is rare but possible by taking large amounts in a supplement form. Taking more supplements simultaneously can sometimes interact with each other (one supplement may strengthen the effects of another). In contrast, in other cases, they might contain one or more of the same nutrients, potentially leading to excess/toxic levels.

Bottom line

We all need high-quality supplements at one point in our lives. Unfortunately, we live in a face-paced world; stress is everywhere, pollution increased, and our soil is not the same as it was. Our nutrient demands increase with illnesses, stress, getting old and expecting a baby. The need for supplements is inevitable, I can safely say!

Be healthy and happy 😊

Gabriella Crust

Gabriella Crust

Nutritional Therapist



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