Source: melanomainternational.org
In the 21st century the demand for dietary supplements has grown substantially, in accordance with the higher standards of living worldwide. People are trying to prolong their lifespan and ensure a better quality of life with use of alternative medicine and natural products such as dietary supplements. There is no doubt that supplements are a good substitute if there is really a deficiency. However, many are unaware of the consequences of taking more than the recommended daily intake and taking supplements together with other commonly prescribed medications.
If one is eating correctly and adequately, it is unlikely that they would need supplements for his or her nutritional needs. Nevertheless there are exceptions, such as illnesses where some supplements may help to alleviate the symptoms or are curative. With that said, one who is perfectly healthy and decides to get supplements should be very cautious not to exceed the recommended daily intake as they can have detrimental effects to our health.
One example is the very common Vitamin D which most people can get from sunlight. Vitamin D has a long list of benefits, ranging from helping the absorption of calcium to even protecting against diabetes, cancer and heart disease as claimed by some researchers. The recommended daily allowance for vitamin D is about 600 International Units (IU) for a fully grown adult up to the age of 70. People aged 71 and beyond should aim for around 800 IU. The Institute of Medicine sets a limit of no more than 4,000 IU per day, as too much vitamin D may lead to higher concentrations of calcium in the bloodstream which may be too much for the heart to handle, leading to heart problems in the future. People who have heart disease or are on medications for the heart such as digoxin should be careful as it may cause irregular heart rhythms.
Another example would be selenium. Selenium is a trace element and is easily obtained from our diet. Major food sources of selenium include bread, grain, meat, fish and eggs. Hence it is quite rare for one to be deficient in selenium. However selenium can be easily found as a stand-alone supplement or in multivitamins. Though selenium may be crucial for DNA synthesis, reproduction, thyroid hormone metabolism and many more, acute selenium toxicity can lead to severe gastrointestinal and neurological effects, heart attack, breathing difficulties, tremors, light-headedness, kidney failure, hair loss and maybe even death. One of the early signs of excess selenium is having a metallic taste in ones’ mouth or garlic breath. Other symptoms include hair loss, nail brittleness, nausea, diarrhoea and skin rashes. Hence all of us must be aware of this.
Currently, there is no concrete evidence that vitamin C has any severe side effects. The few common ones are gastrointestinal disturbances like diarrhoea and abdominal cramps which are due to the osmotic effects of unabsorbed vitamin C. However, there are some studies claiming that vitamin C can cause more serious side effects than just gastrointestinal disturbances. A Women’s Health Study from Iowa showed that postmenopausal women with diabetes who took supplemental vitamin C of at least 300mg/day had an increased risk of cardiovascular disease mortality. Though there is no other study verifying this claim, this finding should not be taken lightly either. Furthermore, chronic consumption of high doses of vitamin C may exacerbate iron overload and cause tissue damage in individuals with hereditary hemochromatosis. This blood disorder is more prevalent in Europeans, Australians and other Western countries.
What about glucosamine and chondroitin? Many know that this combination of supplements help those who are suffering from osteoarthritis. However, do they know about the side effects of these supplements? Common side effects of glucosamine are diarrhoea, constipation and even heartburn. Uncommon ones include drowsiness and headache. Chondroitin on the other hand has reported side effects such as leg swelling, hair loss, swollen eyes and even irregular heartbeat. Many remain unaware of the side effects of the supplements they are consuming and hence think these symptoms are due to an illness, disease or dysfunction of the body.
With growing concerns over the use of supplements and its exponential growth in todays’ market, one should be very careful not to misuse and overuse such supplements as they might not be as beneficial for ones’ health. Aside from knowing the benefits of it, one must know the recommended daily intakes and should be able to identify the signs and symptoms of overdose. When interested in getting supplements, try asking for opinions and recommendations from health care professionals for more accurate information. Most importantly, try not to purchase supplements or even medications online as many are not approved by the Ministry Of Health and such illegal medications may have added components that may be dangerous to our health.
Chong Fui Pin is a pharmacist who works at a Klinik Kesihatan in Melaka.
References
- Office of Dietary Supplements, (2014). Dietary Supplement Fact Sheet: Selenium — Health Professional Fact Sheet. [online] Available at: http://ods.od.nih.gov/factsheets/Selenium-HealthProfessional/ [Accessed 14 Nov. 2014].
- WebMD.com, (2014). Vitamin D Slideshow: Deficiency Symptoms, Foods, Tests, Benefits, and More. [online] Available at: http://www.webmd.com/food-recipes/ss/slideshow-vitamin-d-overview [Accessed 14 Nov. 2014].
- Office of Dietary Supplements, (2014). Vitamin C — Health Professional Fact Sheet. [online] Available at: http://ods.od.nih.gov/factsheets/VitaminC-HealthProfessional/ [Accessed 14 Nov. 2014].
- National Librabry of Medicine – National Institutes for Health.nih.gov, (2014). Chondroitin sulfate: MedlinePlus Supplements. [online] Available at: http://www.nlm.nih.gov/medlineplus/druginfo/natural/744.html [Accessed 14 Nov. 2014].
- Mayoclinic, (2014). Drugs and Supplements : Glucosamine. [online] Available at: http://www.mayoclinic.org/drugs-supplements/glucosamine/safety/hrb-20059572 [Accessed 14 Nov. 2014].
[This article belongs to The Malaysian Medical Gazette. Any republication (online or offline) without written permission from The Malaysian Medical Gazette is prohibited.]