The World Obesity Atlas 2023 projected that over 4 billion people will be living with overweight or obesity by 2035, including about 1.9 billion with obesity.
This will mean a global economic impact of 4.32 trillion annually – similar to COVID-19 in 2020 – reports the Atlas, which is put out by the World Obesity Federation.
The gloomy dataset predicts that 51% of the world’s entire population will be either overweight or obese by 2035 if current trends prevail. And more than 1 in 4 of the world’s population will be obese compared to 1 in 7 today, with obesity rates rising fastest amongst children and adolescents.
“Of these four million people, two million will be obese and many of these will require bariatric specialist surgical interventions,” says Mr Jason Winnett, Melbourne Laparoscopic and Bariatric surgeon.
“However, for many people who are overweight simply losing 5, 10 or 15kg without surgery will be able to reverse significant co-morbidities and GPs in the coming years will play a more crucial role than ever in managing weight and helping patients lose these smaller amounts or for people who do not want to go down the surgery pathway.”
Here are five potential benefits of patients losing just 10% of body weight:
1. Blood sugar levels
In a 2017 Lancet trial of 298 adults with type 2 diabetes in general practice, 46% of those in a structured weight management program, which used a low-energy diet, were in remission at 12 months, compared with 4% of controls.
“GPs and specialists play a big role in weight loss because of regular doctor-based involvement, simply because patients are accountable to someone else other than themselves,” say Mr Winnett.
“As weight gain can also be exacerbated by depression, diabetes, thyroid disease and many other health conditions, being closely involved with someone who has a medical background can help identify issues the patient may not have been aware of.”
2. Fertility
In decades past, weight loss was often not considered in the fertility equation. But according to Melbourne Fertility professional Dr Rachael Knight who performers infertility treatments, gynaecology and laparoscopic surgeries, it’s a vital part of the pregnancy equation.
“Weight loss in the preconception period is important as obesity can cause anovulation, while Polycystic Ovarian Syndrome (PCOS), is a common endocrinopathy that can significantly impair fertility,” says Dr Knight.
“Even in healthy weight, the chance of pregnancy is about 85% in 12 months of regular intercourse before age 30. It’s a downward trajectory from there, dropping to 66% pregnancy rate in 12 months at age 35 and 44% by age 40,” she says.
For overweight women, the battle is even harder. According to one study of more than 600 women in Epidemiology, women with a BMI of more than 27 were three times more likely to be infertile. The good news is that getting “fit for fertility” may improve chances of conception.
A retrospective study found higher conception rates (88% vs 54%) in women who lost 10% or more of their body weight.
Referral to fertility specialist considerations for GP (for overweight women or otherwise) include:
- Recurrent miscarriage and poor pregnancy outcome
- Women over 35, who have been unsuccessful in achieving pregnancy after 12 months of regular unprotected intercourse
- Women over age 36 who have been unable to conceive after 6 months
- Women with PCOS or endometriosis
- Women with irregular cycles
3. Blood Pressure
Every 1kg of weight loss can improve blood pressure (hypertension) by 1 point, the journal Hypertension shows. And Mr Winnett says there are genetic variances for blood pressure too that should be considered.
“We hear a lot about how too much salt can increase blood pressure, but genetic variances in weight are equally important to consider. Some people can put on 10kg and it has no impact on blood pressure, but others have blood pressure that is very “weight sensitive” so gaining or losing 5kg can make a big difference.”
4. Assistance with knee issues
The risk of joint pain goes up incrementally with BMI, and while the knee is most impacted by weight gain, hand and hip arthritis can also be impacted by weight.
A 2018 Arthritis Australia submission into the obesity epidemic in Australia has found that being overweight doubles the risk of knee arthritis, while being obese triples the risk of knee arthritis. It also found that more than half of obese patients undergoing knee replacement have poor outcomes, compared to 10% of healthy weight people.
What is even more concerning is that excess weight in early adulthood increases the risk of arthritis requiring knee replacement by 25%, it found.
5. Cancer Risk
In Australia, the Cancer Council of Australia now directly links obesity to more than 5300 cases of cancer every year.
While 10% weight loss is the goal, even 5% weight loss results in a significantly lower breast cancer risk in post-menopausal women, as reported by the American Society of Clinical Oncology in 2018 in a study containing 930,000 women.
And every 5 point increase in BMI, equates to a 12% increased risk of breast cancer in menopausal women, according to the National Cancer Institute in the US.
What is the link between cancer and obesity?
“Overweight and obesity can cause changes in the body that can expedite cancer,” says Mr Winnett.
“These changes can include long-lasting inflammation and higher than normal levels of insulin, insulin-like growth factor, and sex hormones.”
Sources:
• Reverse Diabetes
GP-Based weight loss program can reverse Type2 diabetes, BMJ 2017.
Primary Led Weight Management for the Remission of Type 2 Diabetes, The Lancet, December 2017.
• Fertility
Excess Weight may affect sperm production, reduce fertility in Men, Harvard School of Public Health
The Conversation, How Does Being Overweight Affect My Fertility?
National Demographic 2023, Does a woman’s fertility really plummet at age 35?
• Blood Pressure
Weight loss and blood pressure control, Hypertension Journal.
Mayo Clinic High Blood Pressure Symptoms and Causes, July 1, 2021
NPS MedicineWise, Understanding Blood Pressure, June 24, 2021
• Joint Pain
• Cancer
Modest weight loss reduces breast cancer risk, Asco Post, 2018
You hold the cards to reducing your cancer risk, Cancer Council Australia
