The safe use of health products for weight loss

An increasing number of Canadians are using health products for weight loss, including prescription drugs and natural health products (NHPs). These products may provide benefits when used properly as part of a weight management program. However, misuse of these products can pose serious risks to your health.

The number of Canadians who are overweight or obese has increased dramatically over the past 25 years. Being overweight or obese increases your risk of developing a wide range of serious diseases and conditions, including high blood pressure, coronary heart disease, Type 2 diabetes, stroke, osteoarthritis, and certain types of cancer, including breast, colon, and endometrial cancer.

As the rate of obesity has increased, so has the market for weight-loss products. Several types of prescription drugs for weight loss are available in Canada. These are intended only for people who are medically at risk due to their weight. In addition, these prescription drugs are intended for use under a health care practitioner's supervision as part of a weight management program that also includes appropriate physical activity and a reduction in the amount of calories consumed.

There are also many different types of natural health products (NHPs) being promoted for weight loss. They are sold over the counter in various retail outlets (e.g., pharmacies, health food stores, grocery stores) and are also available online. Under the right circumstances, some of these NHPs may be safe and effective when used as part of a weight management program that promotes a reduced intake of dietary calories and an increase in physical activity. However, there is no such thing as a magic pill that will make you lose weight effortlessly.

If you are considering the use of health products for weight loss, you should be aware of potential risks so you can make informed choices.

Risks of using health products for weight loss

It is not possible to list the risks associated with every weight-loss product on the market, due to the large number of products available. In addition, the risks of using health products depend on many factors, including:

  • the ingredients of the specific health product;
  • whether the health product is used alone or in combination with other products for weight loss, prescription and non-prescription health products, as well as certain foods; and
  • the age and health status of the person using the product.

However, the following situations represent misuse of weight-loss products, which could lead to serious health effects:

Ordering prescription drugs online that have not been prescribed for you by a health care practitioner who has examined you -

Your health care practitioner needs to examine you to determine whether the benefits of using a prescription weight-loss drug would outweigh the risks in your specific situation.

Taking several different kinds of weight-loss products together , or taking weight-loss products in addition to other health products, without discussing possible risks with your health care practitioner -

Certain kinds of weight-loss drugs and natural health products may interact with each other, with foods you eat, or with other medications you take, increasing the risk of adverse reactions. As well, health products for weight loss may not be recommended for individuals with certain health conditions.

Buying weight-loss products online from unreliable sources -

Anyone can put up a Web site and offer health products for sale. If you order health products from unreliable sources, you have no guarantee that they will be safe, effective, and of high quality. Certain NHPs promoted online for weight loss have posed serious health risks because they have been mixed with prescription drugs or contaminated with heavy metals. Others products ordered online from unreliable sources, including prescription drugs, may be counterfeit, or contain ingredients other than those being advertised.

In some cases, products contain "proprietary" or trademarked/patented blends of ingredients. This makes it difficult to identify the content of each ingredient or determine whether some combination(s) of ingredients could harm your health.

Using health products "off-label" for weight loss, unless this has been recommended by your health care practitioner -

Using a product "off-label" means using it for a purpose other than the authorized purpose(s). Products containing the herb Ephedra (or one of its active ingredients, ephedrine) and the herb bitter orange peel (or one of its active ingredients, synephrine) are often promoted off-label for weight loss. However, Ephedra and ephedrine are authorized by Health Canada as decongestants (conventional or traditional herbal medicines) and in homeopathic medicines. Bitter orange (Citrus aurantium) peel is used in traditional Chinese medicine for several conditions, including abdominal pain and constipation, and is used in food to make marmalade, but it is not authorized for the purpose of weight loss. Synephrine has not been approved for use in any health products to date. Health Canada has issued warnings about the potential risks of using Ephedra/ephedrine and bitter orange/synephrine for weight loss, including serious cardiovascular adverse reactions.

Stimulant laxatives (Senna, Cascara, Aloe) may be authorized for oral use as laxatives, but are often promoted for off-label use in detoxifying or cleansing regimens, which are becoming increasingly popular. However, there are serious risks associated with chronic use of laxatives or combining multiple laxatives together, including the risk of electrolyte disturbances that can affect the heart, as well as create bowel problems.

Assuming that a weight-loss product is "safe" because it is "natural" -

For example, an active component from a food substance can be extracted, concentrated, and manufactured or sold as a natural health product. While the original food may pose no risk when consumed in moderation, there could be significant risks in taking a much higher dose in the form of an extract. This may be true of certain NHPs containing highly concentrated green tea extract, some of which have been associated with serious liver problems, as opposed to the beverage, green tea, which is very safe.

Other considerations

In some cases, product advertisements may make claims that are not supported by sound scientific evidence. For example, there are claims that certain products promote weight loss by suppressing your appetite, increasing your metabolism, or blocking the absorption of carbohydrates or fat. While the products authorized for sale by Health Canada have been assessed and determined to be safe, effective, and of high quality when used for their authorized purposes, some of the unauthorized products may be potentially harmful, while others may simply be a waste of money.

Minimizing your risk

If you are concerned about your weight, talk to your health care practitioner about the best way to achieve and maintain a healthy body weight. Also, see the For more information section for resources that can help you make healthy choices (Eating Well with Canada's Food Guide and Canada's Physical Activity Guide to Healthy Active Living).

If you are considering the use of health products for weight loss, discuss the potential risks with your health care practitioner. This is especially important if you are under the age of 18, or if you are pregnant/lactating, or if you have any medical conditions or serious diseases, such as heart disease, high blood pressure, diabetes, or any other serious chronic conditions. Be sure to tell your health care practitioner about all other health products you are taking, including prescription and over-the-counter drugs, and NHPs, including vitamins, minerals, and other supplements. Also:

  • Only take prescription drugs that have been prescribed for you by a health care practitioner who has examined you.
  • Avoid buying health products online from a source that:
    • refuses to give you a working telephone number and a street address
    • offers to issue a prescription based on answers to an online questionnaire
  • Avoid using health products off-label for weight loss, unless this has been recommended by your health care practitioner.
  • Avoid using multiple health products ("stacking") for weight loss, unless this has been recommended by your health care practitioner.
  • Be sceptical about claims in the advertising for "natural" weight-loss products. If a product sounds too good to be true, it probably is.
  • If you want to be sure that the health products you use have been assessed by Health Canada for safety, effectiveness, and quality, and are authorized for sale in Canada, look for one of the following eight-digit numbers on the package:
    • a Drug Identification Number (DIN)
    • a Natural Product Number (NPN), or
    • a Homeopathic Medicine Number (DIN-HM)
  • If you have an adverse reaction while using any health products for weight loss, contact your health care practitioner right away. Consumers and health care practitioners are also encouraged to notify Health Canada, in confidence, about adverse reactions. See the Need More Info? section for a link to our MedEffect Web site, where you will find contact information, forms, and guidance documents.

Health Canada's role

There is some degree of risk associated with the use of any health product. To minimize risks, Health Canada regulates therapeutic drugs and natural health products to be sold to Canadian consumers through a rigorous licensing process, which includes an extensive pre-market review and the ongoing post-market assessment of the health product's safety, effectiveness, and quality. As part of this work, Health Canada assesses the benefits and risks of health products, monitors adverse reactions, and communicates information about risks to health care practitioners and the public. Through the Health Products and Food Branch Inspectorate, Health Canada is responsible for health product compliance, monitoring, and enforcement activities such as industry inspection and product investigation.

For more information

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