{"id":250772,"date":"2026-01-25T07:15:33","date_gmt":"2026-01-25T07:15:33","guid":{"rendered":"https:\/\/www.newsbeep.com\/nz\/250772\/"},"modified":"2026-01-25T07:15:33","modified_gmt":"2026-01-25T07:15:33","slug":"why-using-weight-loss-jabs-could-have-risks-for-runners-according-to-a-top-sports-dietician","status":"publish","type":"post","link":"https:\/\/www.newsbeep.com\/nz\/250772\/","title":{"rendered":"Why using weight loss jabs could have risks for runners, according to a top sports dietician"},"content":{"rendered":"

Running is a great way to improve your fitness and is one of the most accessible and convenient sports. But there can be a darker side to it. Running can become obsessive and addictive \u2013 it can also become a way that many people attain worth and, in some extreme cases, it can become a \u2018necessity\u2019 to earn food<\/a>. In these cases, running becomes a dysfunctional behaviour with negative consequences<\/a> to both health and performance. <\/p>\n

I\u2019m sure that we all know of someone who, despite all the up-to-date information out there, still buys into the narrative of \u2018lighter makes you faster\u2019. As I have previously discussed in this column, lighter makes you faster until it doesn\u2019t. What I mean by this is that there is a tipping point. Everyone has an optimal place where their body works best for them and when we push it too far, it is no longer sustainable \u2013 both health and performance will deteriorate. <\/p>\n

The rise of GLP-1 jabs<\/p>\n

In recent months, the rise of high-profile individuals admitting to the use of GLP-1 weight loss injections to help them become \u2018healthier and more confident\u2019 has created concern for those of us working in the world of sports medicine, with the worry that many runners may turn to them in an attempt to improve their performance. But what exactly are these GLP-1 injections and how do they work?<\/p>\n

These drugs were first developed as medication for type 2 diabetes<\/a>. They work by acting on the GLP-1 receptors found in the brain and pancreas and delay gastric emptying. They also improve glucose homeostasis, reducing the risk of hyperglycaemia (high blood sugar levels) in those with type 2 diabetes. A common side effect is loss of appetite and this, combined with the slow gastric emptying, results in weight loss.<\/p>\n

So what\u2019s the problem? While they are aimed at a specific population group and intended to be used with wraparound clinical, dietetic and psychological care, they are also readily available via private prescriptions and online pharmacies. Presently, the NHS criteria for a prescription includes those who have a BMI of 40 or higher, or a BMI of 37.5 or higher for those from Black, Asian or other minority ethnic groups, along with a confirmed diagnosis of four or more of the following conditions: type 2 diabetes, high blood pressure, heart disease, abnormal blood fats or obstructive sleep apnoea. There will still be a large number of individuals who have a higher BMI and maybe only one or two of the mentioned conditions that will still benefit from these medications \u2013 they have no choice but to get a private prescription. <\/p>\n

None of the above groups are the concern \u2013 the issue is individuals who don\u2019t meet any of the criteria accessing the drug. There is a huge risk around the safety and appropriateness of prescribing, particularly in people without a clinical indication, including those who are a healthy weight and just want to lose some weight to build confidence or maybe because they believe that it will support their running performance. <\/p>\n

Health is not an aesthetic<\/p>\n

One of the biggest misconceptions around the use of these medications is that they will achieve health. Ideally, they should only be available on prescription after a full clinical assessment to ensure that they do indeed lead to improvements in health metrics and quality of life. In reality 95% of people taking these drugs are buying them on the internet via private prescription, without any need to prove they fit the appropriate criteria. In some cases, these drugs are being purchased from unlicensed online sellers without any guarantee that they even are GLP-1 antagonists. <\/p>\n

Health is more than what we look like. In fact, if you don\u2019t change your lifestyle behaviours around food and exercise, the benefits of weight-loss alone are small. Indeed, studies have shown that after stopping with these medications, two-thirds of weight lost is regained in a year, and there is a return to the starting weight in less than two years.<\/p>\n

I\u2019d go as far as saying participating in healthy behaviours, even if you have a higher BMI or body fat percentage, will still have more benefit to health when compared to those who may have lower BMI and body fat percentage but are sedentary and eat a diet that\u2019s not nutrient-dense. <\/p>\n

Problems with GLP-1 jabs<\/p>\n

There are a number of other concerns that the companies behind these medications don\u2019t report:<\/p>\n

While rapid weight loss may be desired, the negative consequences that this can have on cognition is not discussed. A study in 2017 showed that even 5% rapid weight loss could significantly impact cognition and result in eating pathology linked with eating disorder behaviour. In fact, 25% of women and 50% of men were still considered to have an obese BMI but portrayed anorexic cognition and behaviours.Rapid weight loss, regardless of the final weight, can also lead to a down regulation of endocrine (hormonal) processes, potentially having a serious effect on fertility and bone health. This will be accelerated further if combined with physical activity.There is a higher risk of nutritional deficiencies at intakes below 1200 kcal a day for females and 1800 kcal a day for males. At present, no nutrition guidelines exist to show how best to support individuals using these medications. We do, however, have evidence of nutritional deficiencies with their use and individuals not meeting recommended intakes for vitamins, minerals, protein or fibre, even after a short period of taking them.Although these injections work on a number of mechanisms, one is to slow gastric emptying, which means holding food within the gastric tract for up to 72 hours longer than normal. This leads to all sorts of implications for our gut biome<\/a>, which, in return, will have a negative impact on our mental and immune health.Are there higher risks for runners?<\/p>\n

The use of these injections not only results in a loss of body fat, but also a loss of muscle mass. Runners with higher muscle mass will generally perform better, as muscle supports the overall load of training, bone health and, most importantly, allows for more power and speed. <\/p>\n

My final thought on this is that while it may appear to be a shortcut to health and performance, in the long term there is a lot more risk and possibility of negative consequences \u2013 especially for those of us who do not meet the clinical prescription criteria and are actually already engaging in healthy behaviours.<\/p>\n

Renee McGregor is a leading sports dietitian with over 20 years\u2019 experience. reneemcgregor.com<\/a><\/p>\n

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Renee is a leading Sports dietitian, specialising in Eating Disorders, REDs, The Female Athlete, Athlete health and performance.<\/p>\n","protected":false},"excerpt":{"rendered":"Running is a great way to improve your fitness and is one of the most accessible and convenient…\n","protected":false},"author":2,"featured_media":250773,"comment_status":"","ping_status":"","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[10],"tags":[145764,5218,145765,2117,134,2116,111,139,69,145763],"class_list":["post-250772","post","type-post","status-publish","format-standard","has-post-thumbnail","category-health","tag-according-to-a-top-sports-dietician","tag-content-type-default","tag-contentid-64f2084c-7857-4741-a871-59445aa62a4d","tag-displaytype-standard-article","tag-health","tag-locale-gb","tag-new-zealand","tag-newzealand","tag-nz","tag-shorttitle-why-using-weight-loss-jabs-could-have-risks-for-runners"],"_links":{"self":[{"href":"https:\/\/www.newsbeep.com\/nz\/wp-json\/wp\/v2\/posts\/250772","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.newsbeep.com\/nz\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.newsbeep.com\/nz\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.newsbeep.com\/nz\/wp-json\/wp\/v2\/users\/2"}],"replies":[{"embeddable":true,"href":"https:\/\/www.newsbeep.com\/nz\/wp-json\/wp\/v2\/comments?post=250772"}],"version-history":[{"count":0,"href":"https:\/\/www.newsbeep.com\/nz\/wp-json\/wp\/v2\/posts\/250772\/revisions"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/www.newsbeep.com\/nz\/wp-json\/wp\/v2\/media\/250773"}],"wp:attachment":[{"href":"https:\/\/www.newsbeep.com\/nz\/wp-json\/wp\/v2\/media?parent=250772"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.newsbeep.com\/nz\/wp-json\/wp\/v2\/categories?post=250772"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.newsbeep.com\/nz\/wp-json\/wp\/v2\/tags?post=250772"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}