But here\u2019s the thing that\u2019s rarely acknowledged: weight loss is tremendously difficult \u2013 especially for beginners. It\u2019s believed the majority of diets fail, often within weeks, and studies repeatedly show that people who do lose weight usually put it back on \u2013 and more \u2013 within a couple of years.<\/p>\n
In the UK, two-thirds of adults are overweight. In the US, it\u2019s closer to three-quarters. There\u2019s lots of evidence weight loss could improve the quality and quantity of their lives.<\/p>\n
In 2025, researchers<\/a> found that cutting just five per cent of body mass could lead to improved health markers for people with obesity \u2013 even if they regain some of the weight \u2013 from lower blood pressure and cholesterol to healthier liver function, reduced inflammation and better sleep<\/a>.\u00a0<\/p>\n However, a 2025 study in the journal\u00a0Heart<\/a>\u00a0found that weight fluctuations can be dangerous, increasing the risk of death in obese people with cardiovascular issues.\u00a0<\/p>\n So what\u2019s the answer? Steady, sustainable, successful weight loss, which is about shifting to a healthier overall lifestyle that you can maintain.\u00a0<\/p>\n We\u2019ve spoken to leading experts and sifted through the latest weight-loss research to identify the strategies that genuinely work. Here are six you can try in the first 100 days of a weight-loss effort to boost your chances of long-term success.\u00a0<\/p>\n Know your enemy<\/p>\n When it comes to losing weight, the obstacles aren\u2019t limited to ready meals, fizzy drinks or stuttering willpower. Your real opponent is thousands of years of evolution<\/a>, which have taught our bodies to notice when we start losing weight \u2013 and do something to stop it.<\/p>\n \u201cWhen we have a calorie deficit, our body kind of panics on an evolutionary level,\u201d says Dr Rachel Woods<\/a>, a physiology researcher at the University of Lincoln.<\/p>\n \u201cThere\u2019s evidence to show that when someone starts to lose weight, our body does some annoying things that counteract that.\u201d<\/p>\n These include increasing levels of our hunger hormones and lowering energy expenditure in ways we don\u2019t notice. You might walk around or fidget less, Woods says. \u201cOur bodies get more efficient at burning energy \u2013 and our basal metabolic rate decreases.\u201d<\/p>\n These adaptations evolved to help us in periods of scarcity, but they work against us in the modern world.\u00a0For most of us living in developed countries, energy-dense foods are cheap and plentiful.<\/p>\n \u201cIt\u2019s really easy to eat 500 calories,\u201d Woods says. \u201cYou could do that in a few minutes if you were hungry and had some chocolate bars or whatever you fancy. But to burn 500 calories is so much harder.\u201d\u00a0<\/p>\n That\u2019s why, if you want to lose weight and keep it off, then permanent changes in your nutrition and lifestyle are better than a crash diet \u2013 because when the diet ends, those energy-dense foods are still just as available.\u00a0<\/p>\n Rethink your goals Drastically cut your calorie intake and\/or start exercising much more than usual, and you can lose weight quickly, says Woods.<\/p>\n \u201cIf, hypothetically, you ate a very low-calorie diet of say 600\u2013800 calories a day, you could expect to lose quite a bit of weight,\u201d she says.<\/p>\n \u201cBut realistically, how long can someone sustain that for? We generally recommend people set a target of [losing] about five per cent of their body weight.\u201d<\/p>\n Another way to frame it is to think about where you want to be in three years, rather than three months. Adopt smaller measures that are easier to adapt to and get results over time.\u00a0<\/p>\n \u201cOne approach that often works well is using SMART goals,\u201d says Dr Laura Kudlek<\/a>, a researcher at Cambridge, who is exploring the psychological factors behind weight loss<\/a>.<\/p>\n \u201cThat is, goals that are Specific, Measurable, Achievable, Relevant and Time-bound. Rather than saying \u2018I want to lose weight\u2019, a SMART goal could be \u2018I will go for a 15-minute walk after lunch three times this week\u2019.\u201d\u00a0<\/p>\n Weight loss itself might not be the right measure. If you add muscle while you\u2019re training, your weight won\u2019t fall as quickly, as muscle weighs more than fat.<\/p>\n A shrinking waist circumference, for example, is a good sign you\u2019re losing visceral fat around your internal organs.<\/p>\n Falling blood pressure, lower cholesterol, improved sleep or increased strength at the gym also tell you that whatever you\u2019re doing, it\u2019s working \u2013 because your health is improving.<\/p>\n Read more:<\/p>\n Start lifting weights<\/p>\n There was a time when exercising to lose weight meant one thing: cardio. Walking, running, cycling and aerobic exercise classes were the standard approach, simply because they can burn a lot of calories.<\/p>\n In recent years, however, researchers have shifted their attention away from the treadmill to the weight-lifting section of the gym.\u00a0<\/p>\n \u201cIf you do resistance training, with weights or using your own body weight, you\u2019re going to be building your muscle mass,\u201d says Woods.<\/p>\n \u201cThat means you burn more energy because muscle is very active and it uses a lot of energy. So if you have a higher muscle mass, even when you\u2019re sitting on the sofa, you\u2019ll be burning more energy than if you had a lower muscle mass.\u201d\u00a0<\/p>\n High-intensity strength training, where you push yourself to the limit, also has a kind of \u2018afterburn\u2019 effect. Known as EPOC (excess post-exercise oxygen consumption), the effect leads to an increase in the energy burned for an extended period after your workout ends, as your body works to repair the muscles used.<\/p>\n In a landmark paper from 2002<\/a>, researchers showed the effect continues for a whole 38 hours after your workout.\u00a0<\/p>\n Studies also show that people who do resistance training for weight loss regain less weight than people who don\u2019t do it. This is probably because of the long-term increase in their resting metabolic rate.\u00a0<\/p>\n Weight training can be intimidating for beginners, but the good news is that you don\u2019t have to lift heavy to see results. Research shows<\/a> that lifting lighter weights for more repetitions can have similar effects as lifting heavy weights for fewer reps.\u00a0<\/p>\n Don’t neglect other forms of exercise<\/p>\n All movement matters. That\u2019s the general consensus that underlies most recommendations around healthy weight loss.<\/p>\n Aerobic exercise may trigger your hunger hormones, but research shows it can be highly effective at reducing body fat and waist circumference \u2013 if you do enough.<\/p>\n A 2024 review<\/a> into the existing evidence found that you need a minimum of 150 minutes of vigorous exercise, or 300 minutes of moderate exercise, per week to see clinically meaningful weight loss, assuming you\u2019re not also cutting calories from your diet.\u00a0<\/p>\n![\"Photo](\"https:\/\/www.newsbeep.com\/nz\/wp-content\/uploads\/2026\/04\/100-days-fat-loss-chocolate-weights.jpg\")
It\u2019s really easy to eat 500 calories… You could do that in a few minutes if you were hungry and had some chocolate bars or whatever you fancy – Image credit: Getty Images<\/p>\n
\n![\"Close](\"https:\/\/www.newsbeep.com\/nz\/wp-content\/uploads\/2026\/04\/100-days-fat-loss-exercise-phone.jpg\")
A good approach to fat loss is using SMART goals – Image credit: Getty Images<\/p>\n![\"Close](\"https:\/\/www.newsbeep.com\/nz\/wp-content\/uploads\/2026\/04\/100-days-fat-loss-weights.jpg\")
Research shows that lifting lighter weights for more repetitions can have similar effects as lifting heavy weights for fewer reps – Image credit: Getty Images<\/p>\n
![\"Photo](\"https:\/\/www.newsbeep.com\/nz\/wp-content\/uploads\/2026\/04\/100-days-fat-loss-cycle-class.jpg\")
“The more you exercise, the more you can exercise, and the more you enjoy it” – Image credit: Getty Images<\/p>\n![\"Photo](\"https:\/\/www.newsbeep.com\/nz\/wp-content\/uploads\/2026\/04\/100-days-fat-loss-diet.jpg\")
\u201cIncreasing the amount of plants you eat \u2013 so adding lots of vegetables and fruit and nuts \u2013 makes you more likely to feel full and less likely to eat more energy-dense foods that might increase your weight\u201d – Image credit: Getty Images<\/p>\n![\"Photo](\"https:\/\/www.newsbeep.com\/nz\/wp-content\/uploads\/2026\/04\/100-days-fat-loss-plateau.jpg\")
“We generally recommend people set a target of [losing] about five per cent of their body weight” – Image credit: Getty Images<\/p>\n