A nutrition expert says lasting weight loss requires sustainable, realistic changes—here are five she recommends

Weight loss is a complex and emotive process, with many factors at play that can impact results. And keeping the weight off can be even harder.

“Biologically, our bodies are designed to defend against losing weight,” says Dr Rachel Woods, a senior lecturer in physiology at the University of Lincoln in the U.K.

“When we reduce calorie intake, the body responds by slowing metabolism and increasing hunger signals, essentially trying to conserve energy,” says Woods, who has spent nearly 15 years working in and around health and nutrition research. “This makes sustaining weight loss very difficult.

“On top of this, we live in an environment that poses significant challenges. Busy lives, long working hours and easy access to convenient, energy-dense foods make it hard to adhere to calorie-restricted diets consistently.

“Social pressures, stress and fatigue can also contribute to people choosing less nutritious foods. Together, these biological and environmental factors create a perfect storm that makes weight loss a real challenge for many people.”

And keeping it off can be even harder, says Woods.

“Many people are able to manage the challenges of calorie restriction for a limited period, which is often enough to achieve the initial weight loss they’re looking for. During this time, motivation is high and the effort feels purposeful. However, sustaining the same level of restraint over the long term is so much harder.

“The body continues to resist weight loss, with hunger signals remaining stronger and metabolism slightly slowed. Coupled with the mental and physical effort required to consistently eat differently from your habits or environment, maintaining that calorie deficit over months and years becomes extremely challenging.

“This is why long-term weight maintenance is often harder than the initial weight loss phase, and why sustainable, realistic changes are essential for lasting success.”

So what does Woods recommend as the best approach to losing weight and keeping it off?

“My advice is to focus less on weight itself and more on improving diet and lifestyle for overall health,” says Woods. “Weight loss may follow naturally as a result. If someone specifically wants to lose weight, the key is to adopt habits that are sustainable in the long term.”

Here are the five habits that Woods recommends.

Step one: Eat more plants

“Fruits, vegetables, beans and lentils are nutrient-dense, high in fiber and relatively low in calories. Increasing these foods in your meals helps you feel full and may naturally reduce the intake of higher-calorie snacks,” says Woods.

Step two: Prioritise whole foods over heavily processed ones

“Whole foods are generally more filling, nutrient-rich and less likely to make you overeat. A simple way to identify processed snacks is to check the ingredient list and choose foods made from ingredients you recognise and can pronounce,” she says.

Step three: Reduce alcohol intake

“Alcohol adds extra calories without filling you up and has a negative impact on many areas of health. Cutting back can have a significant impact over time,” says Woods.

Step four: Consider portion adjustments strategically

“Rather than simply eating smaller portions of everything, which can leave you hungry, try increasing your portions of low-calorie, nutrient-dense foods such as fruits, vegetables and salads while moderating higher-calorie items,” says Woods.

Step five: Choose sugar-free drinks or water instead of sodas

“If you drink a lot of sugary beverages, this is an easy swap that reduces calorie intake,” says Woods. “The overarching principle is sustainability. Small, consistent changes are better than drastic restrictions that are hard to maintain.”

What about exercise?

“Diet generally has a larger impact on creating a calorie deficit, but exercise is also incredibly valuable for overall health. It supports cardiovascular fitness, strengthens muscles and bones, improves mood and sleep, and helps manage stress.

“When combined with dietary changes, exercise can help protect against weight regain, support metabolic health and improve body composition—for example, maintaining lean muscle while losing fat. So, while it may not always be the fastest route to weight loss, it’s critical for long-term health and wellbeing.”