I was looking for information on the internet and came across a recent publication discussing Safety and Efficacy of Dietary Supplements for Diabetes (1) and it is this article that inspired me to write today’s topic. By the end of the discussion I hope I have encouraged you to check all the facts before embarking on any new product that you wish to add to your medicine profile.
The use of complimentary and alternative medicines has been rising over the years and with COVID19 pandemic, its use has continued to rise. There may be several reasons for this, one being people have more time to research products on line or they want to do everything in their power to support their immune system and avoid contracting COVID19.
In Canada, Natural health product (NHP) refers to a range of health products such as vitamins and mineral supplements, herbal and plant-based remedies, traditional medicines, homeopathic medicines, omega and essential fatty acids and probiotics. (2) I was surprised to find certain toothpastes, shampoos and antiperspirants as well as other products belonging to this same class because of their medicinal ingredients and intended uses. No doubt we have all been intrigued by some NHP that seems to offer a cure for our ailments. I admit I have probably been a victim of this over the years.
The quarterly retail sales of vitamins, minerals and other health supplements in Canada for the first quarter of 2014 to the 3rd quarter of 2020 is almost 800 million dollars.
It is suggested that 71% of Canadians have used NHP like vitamins, minerals, herbal products and homeopathic medicine and people with diabetes report 25-57% use of supplements.(3)
Everyone has their own reason for taking supplements and this is no different for people with diabetes. Diabetes individuals may decide to indulge in NHP because they believe the word “natural” means it is without risks, concerns over prescribed medication costs, influence and encouragement from family and friends and the desire to further lower their glucose in addition to their traditional medicines.
NHP Regulations in Canada
The commercial sale of natural health products in Canada is subject to the licensing provisions of the NHP Regulations which have existed since 2004. The regulations are meant to assure Canadians have access to products that are safe, of high quality and effective.
A Product License is mandatory for all NHPs to be legally sold in Canada and any site that manufactures, packages, labels and imports these products must have Site Licences.
As with most products permitted for legal sale, the regulations dictate the specific labelling and packaging requirements along with good manufacturing practice standards and the usual evidence that must be met in order to obtain product and Site Licences. (2)
NHPs that are licensed for sale in Canada bear a Natural Product Number (NPN) or Homeopathic Medicine Number (DIN-HM) on the label followed by an eight-diget number (e.g.NPN 12345678). When you find the NPN or DIN-HM on a product you can be assured that this product has been authorized for sale in Canada and is safe and effective when used in *accordance* with the directions on the label. (2)
In 1994, dietary supplements in the United States became regulated under the umbrella of “foods”. (1) This meant that dietary supplements can be marketed without submitting safety data. Like in Canada, manufacturers are required to manufacture their products according to established laws for good manufacturing practices. If the manufacturer makes a claim on how it will affect the condition it is meant to treat, then a printed disclaimer is required by low stating that the claim has not been evaluated by the FDA and the product is not intended to “diagnose, treat, cure or prevent any disease”. (1) In other words, a company cannot claim their product is intended for diabetes treatment, but they can claim that the product helps to maintain healthy blood sugar levels as long as they do not suggest their product can help a consumer with elevated blood sugar. In the real world, realizing this distinction is very difficult for consumers to interpret the consequences of the NHP (supplement).
Clinical trials are mandatory for determining the safety and efficacy of any therapeutic intervention. However, clinical trials are limited for supplements and conclusions are often made from studies of weak quality. Requirements that are needed for approval of prescription drugs such as mechanism of how the drug work, how it is absorbed and used in the body and its toxicity level are lacking for dietary supplements. The lack of this type of information is important to determine if there are any serious toxicities, any risk to diabetes patients and any risk overall to the patient.
The question we must ask ourselves is: “ what about all the claims that manufacturers tell us about how their product will benefit in the treatment of our diabetes?”
First of all, it is extremely important to tell your health care providers if you are using any of these products. There has been a favorable shift in the attitude of practitioners about NHPs over the years. Years ago, there seemed to be quick action to condemn these products, but we know that it shouldn’t be this way and our negative attitude may prevent you, the patient, from disclosing the information we need to help guide you through the choices for good diabetes management or other comorbidities.
Supplements can cause adverse effects, have drug interactions with other medicine you may be taking and you can still experience adverse side effects (toxicity) from these supplements.
Many supplements have been studied to help in the management of diabetes. Sadly, the majority of them have limited data on efficacy and some come with risks in specific populations.
Some issues you may come across when looking for information may include:
1. Safety data is reported for short term use
2. Doses may be above the normal recommended upper limit
3. In a multiple ingredient product, there may be lack of evidence to support all the ingredients use
4. Drug-drug or drug-disease interactions (e.g.flaxseed has potential estrogenic effects and therefore should not be used in women with estrogen receptor-positive breast cancer). A drug-drug interaction could exist between a sedative drug being used for sleep disorders and a supplement that causes drowsiness, therefore additive drowsiness.
5. Another serious drug interaction is the use of some of these products and how they interact with the drug “warfarin” which has multiple uses in medicine. So please if you take warfarin, check with your pharmacist about interaction possibilities.
A good reference on assessing supplementation is the Natural Medicines database.
Some tips on assessing supplementation use may include:
I. Ask yourself why you want to take the supplement; check if there is any evidence for the indication. If you have type 2 maybe the studies, if any, were only done in type 1 patients.
II. Check the dosing schedule and if it seems inappropriate ask your pharmacist or someone you respect and who has knowledge in this area of medical care.
III. Check the list of adverse effects. If side effects such as diarrhea or vomiting/nausea are to occur this could offset your diabetes management causing you to be dehydrated (loose too much body fluid without replenishment) and have consequences on your diabetes.
IV. Have your health care provider do a drug interaction check. If it says it might lower blood pressure and you already take blood pressure medication, then this might lower the blood pressure too much which isn’t good either. There is always the fine balance between good and bad.
V. If you are pregnant, lactating or thinking of pregnancy do your homework before you start any supplement or medicine.
In the Canadian 2018 Clinical Practice Guidelines, Diabetes Canada devotes a section on this topic. One of its key messages is “although some of the therapies may have the potential to be effective, they have not been sufficiently studied and others can be ineffective or even harmful”. Please refer to the guideline document for a more comprehensive review and discussion of products.
So as we move forward and become more engaged in the management of our own health, remember to always do your homework. Check out reliable resources, speak to knowledgeable people and maybe even ask them for their references. Like any other medicine you start, check your blood sugars more frequently, assess how you are feeling each day and until you know the effects be careful doing any hazardous task.
Keep in mind that “natural” doesn’t always mean it is safe for you.
As pharmacists, we do medication reviews and it is surprising how many times when you ask if the person takes any supplements or alternative medicines, they say “oh ya” but these are not medicines, they are natural. These products still get absorbed into the system, get circulated throughout the body and can exert unwanted effects. The lack of efficacy and safety studies in properly designed clinical trials makes it difficult to know the good from the bad.
#supplements&diabetes
References:
1) Safety and Efficacy of Dietary Supplements for Diabetes
2) Government of Canada website- Natural Health Products
3) Diabetes Canada 2018 guidelines
4) PharmacyU newsletter
5) My own knowledge and experiences over my career and life with diabetes
I hope this has been of interest and you will now always tell your health care providers about all medicines that your ingest, even if they are “natural”.
I choose a song today by Nick Jonas who has type 1 diabetes. Apparently he wrote this song in 2008 about his struggle with diabetes. The tune describes the frustrations of such an illness and the patience required while we wait for a cure.
This information is not intended to replace any information provided by your health care team. It is for information purposes only.
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