Obesity rates in Canada jumped during COVID-19, says a new study
The research, published in the Canadian Medical Association Journal (CMAJ) Monday, found that 32.7 per cent of Canadians (10.6 million people) were obese in 2023 — an increase of about eight percentage points since 2009.
But the researchers also saw a steeper increase in obesity during the COVID-19 pandemic.
"The pandemic had such a profound impact on our daily lives … including changes in our eating behaviours and access to healthy foods," said Laura Anderson, lead author on the study and associate professor in health, research methods, evidence and impact at McMaster University in Hamilton, Ont.
Obesity is a medical condition that puts people at higher risk of other serious health issues such as stroke, Type 2 diabetes and certain types of cancer. With frequent lock downs forcing people to stay at home during the pandemic, researchers wanted to see how this changed people's weight.
To study this, Anderson and her team looked at the most recent self-reported body mass index (BMI) data from 746,250 Canadians who were 18 years or older between 2009 and 2023.
The researchers followed the World Health Organization's definition of obesity, classifying someone as such if they had a BMI equal to or higher than 30.
(BMI has its problems as a measure of health; it's not a direct measure of body fat and doesn't account for differences across ethnic groups, sex or gender, for example. But, it's still the preferred measure for researchers looking at groups and population-level trends.)
Before COVID-19, Anderson says Canada's obesity rate was increasing by about 0.5 percentage points per year. But during the pandemic, she says that rate doubled, meaning the obesity rate increased by about one percentage point per year.
While the research didn't look into why this might have happened, Dr. Sean Wharton, an internal medicine doctor who works with people struggling with obesity, says mental health issues could have played a role.
"There was isolation and depression," said Wharton, who did not take part in the new CMAJ study. Wharton says he's a clinical advisor to all of the weight loss drug companies.
"People who were living with depression, their depression may have [gotten] even worse. And that's where we saw people having an increase in their weight."
When asked whether obesity rates will drop now, Wharton says he doesn't think so.
"Once you have that weight gain, it's hard to actually get it off."
Over the 15-year study period and during the pandemic, the greatest increase in obesity was in young adults between the ages of 18 and 39 years old.
And specifically, the research found that an increasing number of women became severely obese, which the authors considered to be a BMI of 40 or higher.
While the study didn't explore the reason behind this, Anderson says it could be that "women had increased stress and burden of other caregiving duties during the pandemic."
And that was the case for Toronto resident Angela Martin.
During COVID-19, she worked as a nurse in a family doctor's office. She also separated from her partner. Between those two events, Martin says 2020 was a hard year.
"Looking back, I was so not fine," she said.
Even though she's struggled with obesity throughout her life, Martin said she gained a significant amount of weight in the early COVID months.
"I mean you did the one thing you could do … you were not prevented from cooking so I tried all new recipes and then you couldn't go to the gym," she said.
While more people became obese in general, the study's authors were most concerned about the rise in people with severe obesity.
In 2009, about 2.4 per cent of Canadians were severely obese, but in 2023 that increased to nearly five per cent.
"With more severe rates of obesity, we're going to see more of the complications," said Wharton.
In particular, he said people are more at risk of illnesses like Type 2 diabetes, osteoarthritis or heart disease.
When looking into other conditions affecting people with obesity, the research found that half of them didn't have any chronic health conditions, but five to 10 per cent had between three to six long-term health problems, such as heart disease, stroke and cancer.
This study looked at data up to 2023, so it's not clear yet what the growing availability of weight-loss drugs like Wegovy — approved last year — may have on obesity rates post-pandemic.
The study notes that may already be changing, but the drugs weren't widely available during their study years.
The researchers didn't dive into this in their study, and won't be able to explore it until more data comes out.
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CNN
23 minutes ago
- CNN
How to make sure you're getting the right supplement. 5 expert tips to help you choose
Editor's note: The podcast Chasing Life With Dr. Sanjay Gupta explores the medical science behind some of life's mysteries big and small. You can listen to episodes here. (CNN) — Take a walk down the supplement aisle of any local drugstore, and you will be confronted with a floor-to-ceiling wall of choices. Not just the usual suspects — vitamins and minerals — but also items as varied as turmeric, fish oil, probiotics and melatonin — as well as combinations that purport to burn fat (not muscle!), cure erectile dysfunction and boost memory. The deluge of options doesn't stop there. Endless social media posts claim a life-changing supplement or regimen will help you eliminate 'cortisol belly,' protect against the flu or 'reset' your hormones. But exactly how many things do we humans need to buy in the race to optimize our health and live our best life? All this noise around supplements generates confusion and anxiety, obscuring what science there is and making it hard to separate fact from wishful thinking. In the most basic sense, these products are meant to supplement the food in your diet with extra added 'dietary ingredients.' You would not be faulted for thinking that the US Food and Drug Administration regulates supplements — and the agency does, but probably not in the way you might think. Thanks to a 1994 law called the Dietary Supplement Health and Education Act, or DSHEA, supplements are regulated more like a subcategory of foods, not a subcategory of medicine. This essentially means that the FDA does not have the authority to approve dietary supplements before they are marketed, unlike pharmaceuticals, which must be shown to be both safe and effective in clinical trials. 'DSHEA is the current framework that all dietary supplements are sold in,' supplement safety advocate Dr. Pieter Cohen told CNN Chief Medical Correspondent Dr. Sanjay Gupta recently on his podcast, Chasing Life. The law, in part, allowed the industry to explode from approximately 4,000 products in 1994, to some 90,000 in 2017, according to estimates in a 2022 AMA Journal of Ethics policy paper. 'Now, that law in 1994 was initially … designed to better regulate vitamins and minerals,' explained Cohen, an associate professor of medicine at Harvard Medical School and an internist at Cambridge Health Alliance, where he leads the Supplement Research Program. 'What unfortunately happened — unfortunately, in my opinion — was that that same structure was expanded to include … all nature of botanicals; many different types of extracts, like, let's say, a cow thyroid extract; live microorganisms, like both bacteria and yeast, that are sold as probiotics; protein powders; amino acids. All this was lumped together under that same framework … and all of them were called 'dietary supplements' or 'dietary ingredients.'' You can listen to the full episode here. The FDA does have some power to take action against supplements that are adulterated or misbranded, but only after they are on the market. 'The FDA is in the position of looking for problems out in the marketplace after supplements are being sold, and then working to try to identify the products, which is incredibly difficult, because they don't have an effective system to detect harms, and then to try to remove those dangerous products,' Cohen said. While regulations exist, 'it's companies selling us whatever they choose to declare and identify as a dietary supplement,' he said. He called it 'a system that emphasizes access and minimizes the assurances of safety or at least leaves safety in the manufacturer's court.' What should consumers do before plunking down money at the health food store? Cohen explains what you should know about product claims and offers five tips when deciding which supplements to buy, keep or toss. How the FDA can and can't regulate the supplement industry doesn't even address the issue of what actually works and what you might actually need. Some studies show certain well-known vitamins or minerals can help particular conditions, but often recommendations change after new information comes to light. Good-quality clinical trials are expensive and hard to conduct (or data are gathered through epidemiological studies, so cause and effect can't be definitively proven); they rarely are done on less-well known (or blended) supplements. The label required on US supplements, in essence, occupies a gray zone, and the average consumer might not know that they are expected to read between the lines. A product label is permitted to contain a claim about the effect of the supplement on the body's structure or function (for example, 'helps support flexibility'). But the label 'may not claim to diagnose, mitigate, treat, cure, or prevent a specific disease or class of diseases,' according to DSHEA. The law allows manufacturers to make those gray-zone, health-adjacent claims as long as they include a disclaimer that the claim has not been evaluated by the FDA. The situation is not likely to change any time soon. 'A core concern I have with the current regulatory framework that really inhibits us moving forward is that there is no incentive for manufacturers to conduct carefully done clinical trials,' Cohen said. 'One thing we haven't talked about yet is that one other part of the law is that supplements can claim to have health effects without it being proven in humans,' he noted. 'Since you can do that without doing a clinical trial, what's the incentive to invest in all that money, millions of dollars, to do a clinical trial? 'The only potential outcome is negative — because if you're right, you were already advertising it as it was beneficial to your health and all you did was to prove that your claim is correct,' he said. 'But more likely, if it turns out it doesn't really work like you had hoped it did, and all that money is wasted, and then you've got a problem. But the good news, I guess, is that you can still keep on selling it as if it does work, even when the studies come out negative.' The FDA has certain best practice rules in place when it comes to manufacturing, but it lacks oversight to ensure what is on the label is actually in the supplement, according to Cohen. That's why it's essential to choose supplements with a discerning eye. 'Toss away all supplements that do not include the official stamps from NSF (NSF International) or USP (US Pharmacopeia),' said Cohen said via email, referring to two independent, not-for-profit agencies that test supplements and then certify them. 'The FDA does not test supplements before they are sold,' he said. 'Unless supplements have been certified by a high-quality third-party organization, such as NSF or USP, it is not possible to know what's really inside the bottle.' 'Both those groups do deep dives into the quality of manufacturing,' Cohen told Gupta on the podcast. 'They look at the original ingredients that are coming (so that) when consumers are going in to purchase this online or in a store, that the label accurately represents what's in the product.' Another reputable third-party tester is But remember, none of these organizations test for efficacy, that is whether a supplement does what it claims to do. 'If you say something's good for gut health or will boost your immunity, those claims are not assessed by these companies,' Cohen told Gupta. 'The companies are just looking at — is the powder in the bottle the same as what's on the label?' A good rule of thumb when checking ingredient lists for supplements is less is more. 'Toss away all supplements that list two or more botanical ingredients on the label,' Cohen said. 'Manufacturers are not required to share the details of each ingredient when mixing multiple botanical ingredients in the same supplement,' he said. For example, you might not know the ratio of one ingredient to the others, how fresh each one is, or the process by which each is prepared and then blended together. 'The only way to ensure that sufficient information about the botanical is provided on the label, (is to) select only single-ingredient supplements,' he added. When you shop for dietary supplements, avoid products that claim in vague language to promote health benefits, Cohen said, such as 'boosts immunity' or 'improves cognition.' 'Supplement claims are not vetted by the FDA, and manufacturers do not need to perform studies of the supplement to demonstrate any benefit before selling the product,' he noted. Cohen said it's best to avoid supplements with these types of claims and instead 'obtain information about benefits and risks of supplements from a reliable, independent source, such as the National Institutes of Health's Office of Dietary Supplements.' Supplements can lose potency or, like fish oil, even go bad. 'Toss away all supplements that are past their expiration date,' Cohen said. 'Supplements past their expiration date are unlikely to have the correct amount of active ingredients as listed on the label,' he explained. It's important to incorporate any supplements prescribed by your doctor in your routine on a consistent basis. Following your annual wellness visit, your physician might say, for example, that you need more iron or vitamin B12 or vitamin D based on bloodwork. 'Take all the supplements that your doctor recommends,' Cohen said. 'Many vitamin and mineral supplements are key to treating a variety of health conditions, so if your doctor recommends one or more supplements, remember to take them regularly,' he said. Most healthy people probably don't need to take even a multivitamin, according to Cohen. 'My clinical experience is that regardless of how people are eating, as long as people are not on a highly restrictive diet, that they are going to get sufficient vitamins and minerals,' he told Gupta. 'Even if they're eating mainly manufactured or processed foods, or they're growing everything in their own garden, because of supplementation (in the food system), I'm not seeing serious vitamin deficiencies in my practice.' Of course, it is not a bad idea to check with your doctor before you start a new supplement, and certainly let them know during your annual exam what you are currently taking. Some supplements can interact with certain medications, while others shouldn't be used by people with certain health conditions. We hope these five tips help you make better sense of supplements. Listen to the full episode here. Join us next week for a new episode of the Chasing Life podcast. CNN Podcasts' Madeleine Thompson and Kyra Dahring contributed to this report.
CNN
35 minutes ago
- CNN
How to make sure you're getting the right supplement. 5 expert tips to help you choose
Prescription drugs Federal agencies New in medicineFacebookTweetLink Follow Editor's note: The podcast Chasing Life With Dr. Sanjay Gupta explores the medical science behind some of life's mysteries big and small. You can listen to episodes here. (CNN) — Take a walk down the supplement aisle of any local drugstore, and you will be confronted with a floor-to-ceiling wall of choices. Not just the usual suspects — vitamins and minerals — but also items as varied as turmeric, fish oil, probiotics and melatonin — as well as combinations that purport to burn fat (not muscle!), cure erectile dysfunction and boost memory. The deluge of options doesn't stop there. Endless social media posts claim a life-changing supplement or regimen will help you eliminate 'cortisol belly,' protect against the flu or 'reset' your hormones. But exactly how many things do we humans need to buy in the race to optimize our health and live our best life? All this noise around supplements generates confusion and anxiety, obscuring what science there is and making it hard to separate fact from wishful thinking. In the most basic sense, these products are meant to supplement the food in your diet with extra added 'dietary ingredients.' You would not be faulted for thinking that the US Food and Drug Administration regulates supplements — and the agency does, but probably not in the way you might think. Thanks to a 1994 law called the Dietary Supplement Health and Education Act, or DSHEA, supplements are regulated more like a subcategory of foods, not a subcategory of medicine. This essentially means that the FDA does not have the authority to approve dietary supplements before they are marketed, unlike pharmaceuticals, which must be shown to be both safe and effective in clinical trials. 'DSHEA is the current framework that all dietary supplements are sold in,' supplement safety advocate Dr. Pieter Cohen told CNN Chief Medical Correspondent Dr. Sanjay Gupta recently on his podcast, Chasing Life. The law, in part, allowed the industry to explode from approximately 4,000 products in 1994, to some 90,000 in 2017, according to estimates in a 2022 AMA Journal of Ethics policy paper. 'Now, that law in 1994 was initially … designed to better regulate vitamins and minerals,' explained Cohen, an associate professor of medicine at Harvard Medical School and an internist at Cambridge Health Alliance, where he leads the Supplement Research Program. 'What unfortunately happened — unfortunately, in my opinion — was that that same structure was expanded to include … all nature of botanicals; many different types of extracts, like, let's say, a cow thyroid extract; live microorganisms, like both bacteria and yeast, that are sold as probiotics; protein powders; amino acids. All this was lumped together under that same framework … and all of them were called 'dietary supplements' or 'dietary ingredients.'' You can listen to the full episode here. The FDA does have some power to take action against supplements that are adulterated or misbranded, but only after they are on the market. 'The FDA is in the position of looking for problems out in the marketplace after supplements are being sold, and then working to try to identify the products, which is incredibly difficult, because they don't have an effective system to detect harms, and then to try to remove those dangerous products,' Cohen said. While regulations exist, 'it's companies selling us whatever they choose to declare and identify as a dietary supplement,' he said. He called it 'a system that emphasizes access and minimizes the assurances of safety or at least leaves safety in the manufacturer's court.' What should consumers do before plunking down money at the health food store? Cohen explains what you should know about product claims and offers five tips when deciding which supplements to buy, keep or toss. How the FDA can and can't regulate the supplement industry doesn't even address the issue of what actually works and what you might actually need. Some studies show certain well-known vitamins or minerals can help particular conditions, but often recommendations change after new information comes to light. Good-quality clinical trials are expensive and hard to conduct (or data are gathered through epidemiological studies, so cause and effect can't be definitively proven); they rarely are done on less-well known (or blended) supplements. The label required on US supplements, in essence, occupies a gray zone, and the average consumer might not know that they are expected to read between the lines. A product label is permitted to contain a claim about the effect of the supplement on the body's structure or function (for example, 'helps support flexibility'). But the label 'may not claim to diagnose, mitigate, treat, cure, or prevent a specific disease or class of diseases,' according to DSHEA. The law allows manufacturers to make those gray-zone, health-adjacent claims as long as they include a disclaimer that the claim has not been evaluated by the FDA. The situation is not likely to change any time soon. 'A core concern I have with the current regulatory framework that really inhibits us moving forward is that there is no incentive for manufacturers to conduct carefully done clinical trials,' Cohen said. 'One thing we haven't talked about yet is that one other part of the law is that supplements can claim to have health effects without it being proven in humans,' he noted. 'Since you can do that without doing a clinical trial, what's the incentive to invest in all that money, millions of dollars, to do a clinical trial? 'The only potential outcome is negative — because if you're right, you were already advertising it as it was beneficial to your health and all you did was to prove that your claim is correct,' he said. 'But more likely, if it turns out it doesn't really work like you had hoped it did, and all that money is wasted, and then you've got a problem. But the good news, I guess, is that you can still keep on selling it as if it does work, even when the studies come out negative.' The FDA has certain best practice rules in place when it comes to manufacturing, but it lacks oversight to ensure what is on the label is actually in the supplement, according to Cohen. That's why it's essential to choose supplements with a discerning eye. 'Toss away all supplements that do not include the official stamps from NSF (NSF International) or USP (US Pharmacopeia),' said Cohen said via email, referring to two independent, not-for-profit agencies that test supplements and then certify them. 'The FDA does not test supplements before they are sold,' he said. 'Unless supplements have been certified by a high-quality third-party organization, such as NSF or USP, it is not possible to know what's really inside the bottle.' 'Both those groups do deep dives into the quality of manufacturing,' Cohen told Gupta on the podcast. 'They look at the original ingredients that are coming (so that) when consumers are going in to purchase this online or in a store, that the label accurately represents what's in the product.' Another reputable third-party tester is But remember, none of these organizations test for efficacy, that is whether a supplement does what it claims to do. 'If you say something's good for gut health or will boost your immunity, those claims are not assessed by these companies,' Cohen told Gupta. 'The companies are just looking at — is the powder in the bottle the same as what's on the label?' A good rule of thumb when checking ingredient lists for supplements is less is more. 'Toss away all supplements that list two or more botanical ingredients on the label,' Cohen said. 'Manufacturers are not required to share the details of each ingredient when mixing multiple botanical ingredients in the same supplement,' he said. For example, you might not know the ratio of one ingredient to the others, how fresh each one is, or the process by which each is prepared and then blended together. 'The only way to ensure that sufficient information about the botanical is provided on the label, (is to) select only single-ingredient supplements,' he added. When you shop for dietary supplements, avoid products that claim in vague language to promote health benefits, Cohen said, such as 'boosts immunity' or 'improves cognition.' 'Supplement claims are not vetted by the FDA, and manufacturers do not need to perform studies of the supplement to demonstrate any benefit before selling the product,' he noted. Cohen said it's best to avoid supplements with these types of claims and instead 'obtain information about benefits and risks of supplements from a reliable, independent source, such as the National Institutes of Health's Office of Dietary Supplements.' Supplements can lose potency or, like fish oil, even go bad. 'Toss away all supplements that are past their expiration date,' Cohen said. 'Supplements past their expiration date are unlikely to have the correct amount of active ingredients as listed on the label,' he explained. It's important to incorporate any supplements prescribed by your doctor in your routine on a consistent basis. Following your annual wellness visit, your physician might say, for example, that you need more iron or vitamin B12 or vitamin D based on bloodwork. 'Take all the supplements that your doctor recommends,' Cohen said. 'Many vitamin and mineral supplements are key to treating a variety of health conditions, so if your doctor recommends one or more supplements, remember to take them regularly,' he said. Most healthy people probably don't need to take even a multivitamin, according to Cohen. 'My clinical experience is that regardless of how people are eating, as long as people are not on a highly restrictive diet, that they are going to get sufficient vitamins and minerals,' he told Gupta. 'Even if they're eating mainly manufactured or processed foods, or they're growing everything in their own garden, because of supplementation (in the food system), I'm not seeing serious vitamin deficiencies in my practice.' Of course, it is not a bad idea to check with your doctor before you start a new supplement, and certainly let them know during your annual exam what you are currently taking. Some supplements can interact with certain medications, while others shouldn't be used by people with certain health conditions. We hope these five tips help you make better sense of supplements. Listen to the full episode here. Join us next week for a new episode of the Chasing Life podcast. CNN Podcasts' Madeleine Thompson and Kyra Dahring contributed to this report.
Yahoo
an hour ago
- Yahoo
Statens Serum Institut Large Danish Study Finds No Link Between Vaccines and Autism or 49 Other Health Conditions
COPENHAGEN, Denmark, July 15, 2025--(BUSINESS WIRE)--A new Danish study finds no association between aluminum in childhood vaccines and 50 different health conditions, including autism, asthma, and autoimmune diseases. The findings reaffirm the safety of Denmark's childhood vaccination program. An extensive new Danish register-based study - the largest of its kind - supports the safety of the national childhood immunization program. Analyzing data from over 1 million children, the study found no increased risk of autism, asthma, or autoimmune diseases in vaccinated children. "Our results are reassuring. By analyzing data from more than one million Danish children, we found absolutely no indication that the very small amount of aluminum used in the childhood vaccination program increases the risk of 50 different health outcomes during childhood," says Anders Hviid, Head of Department at Statens Serum Institut (SSI) and principal investigator on the study. Aluminum, used as an adjuvant to enhance the immune response, has been a component in some vaccines since the 1930s. Researchers from SSI used Denmark's unique national health registers to follow children born between 1997 and 2018, investigating the associations between aluminum-containing vaccines and a total of 50 health outcomes - including asthma, allergies, autoimmune conditions, and neurodevelopmental disorders. "This is the first study of this scale and with such comprehensive analyses, and it confirms the strong safety profile of the vaccines we've used for decades in Denmark," says Anders Hviid. The results are being published at a time of heightened international debate about vaccine safety which makes the Danish study highly relevant. "In an era marked by widespread misinformation about vaccines, it is crucial to rely on solid scientific evidence. Large, population-based register studies like this one - tracking more than a million children over many years - are a bulwark against the politicization of health science which undermines public trust in vaccines. It is absolutely essential to distinguish real science from politically motivated campaigns - otherwise, it is the children who will end up paying the price," says Anders Hviid. Reference: Andersson NW, Bech Svalgaard I, Hoffmann SS, et al. Aluminum-adsorbed vaccines and chronic diseases in childhood. A nationwide cohort study. Ann Intern Med. 15 July 2025. [Epub ahead of print]. doi:10.7326/ANNALS-25-00997 Fact Box: Researchers from Statens Serum Institut (SSI) used Denmark's unique health registers to analyze data from more than 1 million Danish children born between 1997 and 2018 to investigate potential long-term health effects of aluminum-containing vaccines. The study examined 50 different conditions and found no statistical association between aluminum content in vaccines and increased risk of developing autism, autoimmune diseases, asthma, or allergic conditions such as hay fever and food allergies. The study has just been published in the prestigious medical journal Annals of Internal Statens Serum Institut (SSI) View source version on Contacts Anders Hviid, aii@ Error while retrieving data Sign in to access your portfolio Error while retrieving data Error while retrieving data Error while retrieving data Error while retrieving data
