Understanding Suppements

Understanding Suppelments

Supplements (otherwise known as food supplements, dietary supplements or nutritional supplements) include multi-vitamin, single vitamin, single mineral, herbal preparations, oils, liquids and nutraceuticals that increase the presence of substances normally found in the dietary.

They are available in a variety of forms including tablets, capsules, powders and liquids and are usually taken orally to be absorbed through the digestive tract.

Traditionally supplements were only given to individuals if they were deficient as a result of poor intake, poor absorption or excessive excretion.

For example, young women with heavy menstrual bleeding typically lose greater amounts of iron which often results in symptoms of anemia.

This can be addressed through increased intake of iron through the diet but may not adequately address the iron deficiency therefore requiring the use of supplementation.

Supplements are usually only needed temporarily although they can be used for longer term if there is a chronic health condition. 

Supplements are becoming increasingly common and are now found on supermarket shelves all across the world. In the US, the use of supplements ranged between 64% – 69% between 2007 and 2011.

While multivitamins remained the most commonly used supplement (71% of responders), this number actually declined in favour of more people using a variety of supplements.

Typically, women report higher use of supplements compared to men.

Further research has shown that females who are older with better education are more likely to have healthier lifestyle habits and better health status. Unsurprisingly, many marketing strategies are therefore targeted at this demographic. 

While the goal of self-care and personal health advocacy is admirable, it is not without potential dangers.

For example many people may be have co-morbidities (other health issues going on at the same time) and may not understand how supplements may work with these issues or worse still, with medications.

Capitalising on this confusion is clever marketing and multi-level-marketing schemes that target unsuspecting and vulnerable population groups.

This is evidenced by sales of supplements in Australia exceeding more than $646 million dollars in 2013. 

Many people who use supplements have been shown to have a better health status but that is not solely because of their supplement use.

In fact, many people who take supplements unknowingly exceed the recommended upper intake limits which may actually cause or exacerbate health conditions.

While there are many high quality studies that show the benefits of supplementation for the treatment of specific diseases, it is important to note that there are many dangers with supplementation. Particularly as a result of:

  1. Excessive dosage
  2. Poor quality of supplement
  3. Incorrect timing of dosage
  4. Incorrect use of supplement for a condition 
  5. Contraindications with medications

In conclusion, the use of supplements can be highly beneficial to specific groups of people who may be at higher risk of developing deficiencies or who may have higher requirements but use of supplements should always be done with caution and with professional guidance. 


  • Burnett, A. J., Livingstone, K. M., Woods, J. L., & McNaughton, S. A. (2017). Dietary Supplement Use among Australian Adults: Findings from the 2011-2012 National Nutrition and Physical Activity Survey.Nutrients, 9(11), 1248. https://doi.org/10.3390/nu9111248
  • Dickinson, A., Blatman, J., El-Dash, N., & Franco, J. C. (2014). Consumer usage and reasons for using dietary supplements: report of a series of surveys.Journal of the American College of Nutrition, 33(2), 176–182. https://doi.org/10.1080/07315724.2013.875423 
  • Grace, S., Bradbury, J., Avila, C., & Chesne, A. (2018). ‘The healthcare system is not designed around my needs’: How healthcare consumers self-integrate conventional and complementary healthcare services. Complementary Therapies in Clinical Practice, 32. https://doi.org/10.1016/j.ctcp.2018.06.009 

What To Look For In Supplements

As a general rule, supplements come under the governance of national regulatory bodies.

For example, in the USA, the Food and Drug Administration (FDA) is responsible for ensuring that supplement manufacturers meet Current Good Manufacturing Practices.

This is designed to ensure that products are of a good quality and safe however compliance is not always enforced and the FDA does not evaluate the effectiveness, safety or quality of the supplements before they are available for consumers. 

In Australia, the Therapeutic Goods Administration (TGA) is responsible for the oversight of supplementation. 

The TGA regulates the safety and quality of supplements (known as lower-risk medicines) by limiting the ingredients to those that are pre-approved and proven to be low-risk.

These supplements are only to be used for minor health conditions and manufactured in accredited facilities.

The TGA also requires that manufacturers must present evidence of their products’ safety and efficacy.

All medicines in Australia are assigned either an AUST R or AUST L number to further demonstrate that they have met Australian standards.

AUST R numbers are for registered medicines that have been tested for safety, quality and efficacy, while AUST L numbers are for low-risk medicines that are only regulated for safety and quality. 

Due to the differences in regulation, there can be a huge scope for supplement quality and efficacy.

For Australian consumers, ensuring that supplements have an AUST R or AUST L number is a fast and effective way to ensure they are of decent quality.

However, due to manufacturing costs, there is still a wide scope of supplemental quality that may impact on the quality of the product.

Things to be aware of include:

  1. Celebrity or paid endorsements
    These have no bearing whatsoever on the safety or efficacy of a product.
  2. Tricky advertising
    For example many children’s multivitamin supplements have minimal nutritional benefit and as they are aimed at children are often in gummy forms that are coated with sugar which negates any potential health benefit. 
  3. Multi-Level Marketing products
    While some of the research behind these products may be sound, the way these products are marketed raises some serious questions. For example, the cost of the products are often inflated beyond reasonable cost and are sold by people who are more interested in wealth then health. Often they have no background or training in health making them a danger to those who have multiple co-morbidities or who are on multiple medications who need to be managed carefully. 
  4. Low levels of ingredients 
    Ideal levels of Vitamin D should be around 75 – 100 ngl/ml with suggested daily intakes around 1000 IU however many supplements offer doses way beyond this. Even taking into account daily food intakes and sun exposure, many supplements simply are not providing adequate levels of their stated ingredient to provide any health benefit. 
  5. Poor choices of ingredients
    This is particularly true of mineral supplementation where forms used does make an impact on absorption and efficacy. For example the mineral magnesium has been show to be important for muscle relaxation, neuromuscular junction activity, protein  and fat synthesis, energy production and removing excess ammonia through the body. Because of this research there are many different kinds of magnesium products on the market. These include amino acid chelates, oxides, citrates, orotates, chlorides, sulfates, lactates, carbonates and glycinates. Magnesium oxide or heavy magnesium is one of the cheaper forms of magnesium and therefore very enticing for manufacturers to use in their formulations however, it’s bioavailability (it’s uptake by the body) is only 4%, furthermore it can have strong laxative effects. As a general rule, amino acid chelates work best for muscle cells as the body will take it up as a protein. Citrate forms are lower in concentration but have much higher bioavailability at 90% and have been shown to impact pH levels making them ideal for people who suffer form stress. 
  6. Excipients and allergens
    Many people prefer to take their supplements in tablet or capsule forms which leaves them open to taking in excipients (binding agents / colours / fillers etc) that negatively impact health, reduce the effectiveness of the product and inflate the cost of the product unnecessarily. For people who are sensitive or who may have allergies, it is very important to check all excipients for known allergens. Most manufacturing companies will state where the product is made along with excipients and make known what is excluded. For example, this might include no genetically modified products (non GMO), no wheat, no yeast, no gluten, no lactose etc. 


How to Get the Most Out of Supplements

For many people, supplements are bought on a whim, taken religiously for a few days and when no miracle cures appear they are often relegated to the back of the cupboard.

For other people, supplements become a way of life with new additions constantly added to their daily routine.

In both these scenarios, the supplements are not being used well. If you have a multitude of supplements, go through your stock and discard anything out of date.

If you have a garden, many of these supplements can be put together in a bucket of hot water to dissolve and can then be used to fertilise the garden.

Supplements left should be grouped according to function (i.e. Multi vitamin, fish oils, magnesium etc).

Routines can then be created to ensure supplements are used and not abused. 

An important thing to remember is to always go back to basics: supplements are designed to supplement a diet because there is a lack, poor absorption or hyper excretion.

The first choice should always be to ensure a good high quality diet that is rich in vegetables, fruits, lean protein sources, complex carbohydrates and essential fatty acids.

Supplements should only ever be used temporarily.

As a general rule, there is not much safety data for long term supplementation and there is a real risk for many people to exceed known safe limits. 

For that reason, it is best to use new supplements for a month at a moderate dose (follow the instructions on the supplement or by your practitioner) and then take a week off.

As a general rule, I also like to ensure that the supplements are taken with meals as it ensures there is a buffer for sensitive individuals and the supplement will be taken up as part of a food source mimicking natural processes.

After the supplement has finished, it is wise to take a week off as it allows: 

  1. Individuals to see what affect the supplement had (did they feel better / worse)
  2. Individuals to see if the issue has now been resolved
  3. The liver to rest

Where multiple supplements are being used, it is a good idea to total the sum of same ingredients to ensure limits aren’t breached.

It is also wise to understand how each supplement works, for example formulas with B vitamins are good for energy production and stress management making them ideal to take in the morning, while magnesium formulas and some herbs are designed to encourage rest making them better suited for night time use.

Formulas with zinc should be taken with food to avoid nausea while fat soluble vitamins (A, D, E and K) should be taken with meals to improve uptake and absorption.

For athletes and people taking pre-workout products supplements are often promoted to enhance performance, speed recovery, increase fat burning and/or muscle growth.

As a general rule, the studies on these products and combinations is limited, inconclusive and conflicting.

Worse, many of these products are high in sugar and caffeine which can lead to gastrointestinal distress, cardiac arrhythmias, blood pressure increases and destabilise blood glucose metabolism.

For those wanting to look at sports supplementation, it is much better to seek professional advice which may be individually tailored. Otherwise consider food sources such as bananas which have been shown in one randomized, cross over trial involving professional cyclists to attenuate inflammation and improve performance.

Another trial demonstrated that bananas and blueberries were independently shown to have significant reductions in post-exercise inflammation.

One systematic review looked at the impact of cow’s milk on exercise performance and recovery and found some evidence suggesting cow’s milk was associated with improved rate of force, peak torque for knee flexion and reduced soreness 72hours after resistance exercise.

In summary, supplementation is a convenient, cost effect way to ensure nutritional needs are met when dietary intake is compromised however it is not without its challenges.

Rather than adopting a polypharmacy approach, it would be better to consider what individual needs are and then to ensure supplements taken are of a high standard and can fit these requirements.

Taking too many supplements at the same time may lead to confusion over which supplement is eliciting an effect so splitting up doses may be beneficial. 


  • Nabavi, S. M., & Silva, A. S. (Eds.). (2018). Nonvitamin and nonmineral nutritional supplements. Academic Press.
  • Anne E. Eudy, Lindsay L. Gordon, Brandon C. Hockaday, Daniel A. Lee, Vivianne Lee, Daniel Luu, Carlos A. Martinez, Peter J. Ambrose, Pharm.D., FASHP, Efficacy and safety of ingredients found in preworkout supplements, American Journal of Health-System Pharmacy, Volume 70, Issue 7, 1 April 2013, Pages 577–588, https://doi.org/10.2146/ajhp120118
  • Nieman, D. C., Gillitt, N. D., Sha, W., Esposito, D., & Ramamoorthy, S. (2018). Metabolic recovery from heavy exertion following banana compared to sugar beverage or water only ingestion: A randomized, crossover trial. PloS one, 13(3), e0194843. https://doi.org/10.1371/journal.pone.0194843
  • Nieman, D. C., Gillitt, N. D., Chen, G. Y., Zhang, Q., Sha, W., Kay, C. D., Chandra, P., Kay, K. L., & Lila, M. A. (2020). Blueberry and/or Banana Consumption Mitigate Arachidonic, Cytochrome P450 Oxylipin Generation During Recovery From 75-Km Cycling: A Randomized Trial. Frontiers in nutrition, 7, 121. https://doi.org/10.3389/fnut.2020.00121

Supplements and Medications – A Question of Safety

Despite their popularity, supplements should be taken and treated with great respect.

There seems to be a belief that supplements are inherently safe just because they are natural and that is a dangerous fallacy.

All vitamins and minerals have a tolerable upper intake level (UL) beyond which, negative side effects may occur. This is particularly true for fat-soluble vitamins which can be stored in the body.

For example excessive amounts of vitamin A have been linked to birth defects, increased intracranial pressure, dizziness, nausea, headaches, skin irritation, joint pain, coma and even death.

Even after the excessive intake has stopped, in some cases, the damage done to the liver is irreversible. 

When taking supplements with medications, the risk for further complications increases. In one study of more than 3000 elderly people, more than 74.2% were consuming at least one prescription medication with at least one complementary medicine supplement.

Another study suggested that of 197 participants, 45% had the potential for adverse interactions with 6% of these being rated as serious.

Of particular concern are herbal supplements which are highly complex and prone to interact with similar metabolic pathways as many drugs.

A good example is St John’s Wort which has been shown to be effective for the treatment of mild to moderate depression and has low rates of side effects.

According to one systematic review, the use of St John’s wort was able to decrease the bioavailability of some drugs by more than 20%, making them less effective. 

St John’s Wort is not isolated with many other supplements showing an ability to decrease the effectiveness of medications.

Some of these include calcium, celery seed and ginseng.

Other herbs have shown the opposite ability – increasing the effects of drug effects such as selenium and warfarin, olive leaf and antihypertensive drugs and valerian and central nervous system depressants.

Great care needs to be taken with any herbs that impact hormones, particularly if the individual is also on oral contraceptives.

Some herbs such as vitex agnus-castus have been shown to reduce the efficacy of oral contraceptives which may have undesired side-effects. 

Given this is an emerging trend, much more research needs to be done in assessing the safety of supplements with medications.

To ensure safety consider:

  1. Telling your doctor what supplements you are on
  2. Telling your naturopath / nutritionist / herbalist what medications you are on
  3. Ensure all supplements are of good quality and from trusted sources
  4. Take all supplements at least 3 hours away from medications with food
  5. Keep supplementation use to a minimum and rotate supplements or ensure you have two consecutive days off supplements 
  6. Double check safety of herbs and drugs using known qualified resources such as https://reference.medscape.com/drug-interactionchecker or https://www.blackmoresinstitute.org/interactions 
  7. Take medications and supplements as directed only 
  8. Check expiry dates of medications and supplements
  9. Note any ill side effects after taking medications or supplements


  • Gaster, B., & Holroyd, J. (2000). St John’s wort for depression: a systematic review. Archives of internal medicine, 160(2), 152-156.
  • Healthline (2020) How to Choose High Quality Vitamins and Supplements. Accessed on 2/05/2021 from https://www.healthline.com/nutrition/how-to-choose-high-quality-vitamins-and-supplements 
  • Mills, E., Montori, V. M., Wu, P., Gallicano, K., Clarke, M., & Guyatt, G. (2004). Interaction of St John’s wort with conventional drugs: systematic review of clinical trials. Bmj, 329(7456), 27-30.
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