Losing even a small amount of weight can make a big difference. Photo / 123RF
Being overweight or obese has been proven to significantly increase the risk of developing serious health conditions.
In May, a landmark study presented at the European Congress on Obesity, in Dublin, outlined the true cost of obesity to the NHS, revealing that the health service could save £14 billion ($29 billion) a year if everyone were a healthy weight. Obese patients were found to cost the NHS twice as much as those of a healthy weight.
Weight loss is a vital public-health issue, but the personal benefits are equally great. Being overweight or obese has been proven to significantly increase the risk of developing serious health conditions, including cancer, heart disease and type 2 diabetes, among others.
The good news is that losing even a small amount can make a big difference. A 2016 study published in the journal Cell Metabolism found that losing 5 per cent of body weight was enough to significantly reduce the risk of common diseases in a sample of 40 obese adults. In practice, this means the average British man (who weighs 85.4kg, according to NHS data) would need to lose about 4.27kg; for the average woman (72.1kg), it is 3.6kg.
“Five per cent is a good target to be aiming for, and it’s possible to achieve over about a 12-week period for many people, depending on your starting body weight,” says consultant endocrinologist Dr Saira Hameed. And, she says, you will feel the benefit in every area of your life. “Your mobility will improve; your physical fitness will improve; it will take pressure off your back, your hips and your knees,” she says. “Losing 5 per cent of body weight also has metabolic advantages in lowering cholesterol, blood sugar and blood pressure.”
Here are the key life-changing health benefits of dropping half a stone.
A large number of scientific studies have linked obesity with an elevated risk of 13 types of cancer, including bowel, breast and thyroid. In fact, obesity is now responsible for more cases of certain cancers than smoking, according to Cancer Research. “When you lose weight, you lower your cancer risk,” says Dr Hameed, “and if you have had cancer before, that’s even more of a reason to look at losing weight going forward.”
There are various reasons for this, but it is partly because excess body fat can cause levels of growth hormones to rise. “If we’re talking about hormone-driven cancers, such as breast cancer, having higher oestrogen levels can stimulate the growth of cancer cells,” explains Dr Hameed. Breast cancer is the most common cancer in women in the UK, accounting for about 30 per cent of overall cases.
A 2019 study published in the Journal of the National Cancer Institute found that women who lose excess weight in middle age can lower their breast-cancer risk by up to 26 per cent. Even modest weight loss makes a difference: women who lost between 2kg and 4.5kg reduced their risk by 13 per cent.
The second factor is insulin resistance. “When we are overweight or obese, we also tend to have high insulin levels, in association with being insulin resistant. Insulin is a growth factor for normal healthy cells, but also cancer cells, so that plays a part,” says Dr Hameed.
“When you’re overweight or obese, you are in a low-level state of chronic inflammation, as cytokines [proteins that help regulate inflammation] are released directly by body fat, and they probably also play a role in the development of cancer.”
That is why people with type 2 diabetes are at increased risk: recent research from the London School of Hygiene & Tropical Medicine found that the risk of dying from any type of cancer is 18 per cent higher among people with type 2 diabetes than it is in the general population.
Cardiovascular diseases (CVDs) are the leading cause of death globally, and more than four out of five CVD deaths are due to heart attacks and strokes. Excess weight and obesity can lead to high cholesterol and blood pressure, both of which can contribute to heart disease.
Again, there are multiple factors at play, says Dr Hameed. “Your heart is a particular size, and it’s designed for what your body weight and body size should be. If you’re a lot bigger than that, it puts a huge strain on your heart,” she says.
“It’s like a Mini, which has a small engine. If you were to take that engine and put it in a much larger vehicle, it would be under strain, and it’s the same with your heart, so overweight and obesity lead to high blood pressure.” High cholesterol and insulin resistance can also damage blood vessels, she says, which can lead to coronary artery disease. “And then, of course, if you have diabetes, that’s another cardiac risk factor. Losing weight addresses all of this.”
Being overweight or obese is a key risk factor for developing type 2 diabetes, which occurs when the body does not produce enough insulin, resulting in high blood-sugar levels.
In turn, type 2 diabetes is linked with an increased risk of other serious health conditions. “It is a condition in its own right, but it is also a warning sign, as there are so many comorbidities associated with it,” says Dr Mark Cortnage, a senior lecturer in public health at Anglia Ruskin University. “One of the most significant is cancer, but there is also a risk of [developing] dementia, and occasionally depression.”
However, weight loss has been proven to put type 2 diabetes in remission. Research led by the diabetes expert Roy Taylor, professor of medicine and metabolism at Newcastle University, showed that a low-calorie diet and weight-management programme put diabetes into remission in 46.5 per cent of people, and of those, 70 per cent were still in remission two years later.
“The people who’ve got rid of diabetes no longer need to take tablets, and have a really revolutionised approach to life – they have returned to full health,” Prof Taylor previously told the Telegraph. “Even for the people who lost remission, there were advantages.”
When documenting the number of people who were subsequently admitted to hospital for any reason, the rate in the weight-loss group was half that of others with type 2 diabetes, suggesting that weight loss reduced the chance of illness overall. “In terms of avoiding all sorts of problems, including cancers, we found there was a clear benefit of weight loss,” he said.
Excess weight is an important risk factor in osteoarthritis, which affects about 8.5 million people in the UK, particularly in weight-bearing joints such as the knees and hips.
The reason for this is simple: “If you put a huge amount of pressure through the skeleton because of carrying excess weight, your risk of osteoarthritis will be much higher,” says Dr Hameed.
“The problem is, if you develop osteoarthritis, and you have obesity, many orthopaedic surgeons will be reluctant to offer you a joint replacement, because the joint will simply wear out, just like your own,” she says.
“Weight loss will help with osteoarthritis, and sometimes you might not even need joint replacement – simply by losing weight, your own joints have much less pressure through them and you’re in less pain.”
In 2022, NHS guidance changed to prioritise telling arthritis patients to exercise and lose weight over prescribing them painkillers. Over-60s who exercise suffer 25 per cent less joint pain than those who are sedentary, according to a study published in Arthritis Research & Therapy.