When it comes to weight loss, many people believe that hitting the gym or running miles each day is the key to shedding pounds.

Whilst exercise offers countless health benefits, relying on it for weight loss doesn’t work. The government and NHS advice is unscientific. If you want to lose weight, your key focus needs to be on nutrition — not calorie counting — rather than trying to “burn off” excess energy through exercise alone.

Here's Why:

Exercise Accounts for a Small Portion of Daily Energy Usage
100% of the energy you take in comes from food and drink, whereas physical activity accounts for just 10-30% of your daily energy usage, depending on your genetics. Most of your energy expenditure (60-80%) goes towards your basal metabolic rate — the energy required for basic bodily functions.

A study of the Hadza tribe in Northern Tanzania — one of the last remaining hunter-gatherer societies — found that despite their highly active lifestyles (with men walking around 8 miles per day and women 5 miles per day), they burned roughly the same amount of energy as Westerners who spend much of their time sitting. This suggests the body compensates for increased activity by conserving energy elsewhere.

This means that whilst you are 100% in control of your energy intake, the amount of energy available to be used by exercise is relatively small.

You Can’t Outrun a Poor Diet
A single slice of pizza can contain 300 calories, while a 30-minute jog burns roughly the same amount. Many people overestimate the calories they burn through exercise and underestimate how much they consume. Furthermore, all calories are not equal — 300 calories from pizza will have a vastly different effect on the body than 300 calories from chicken.

High-Intensity Exercise and Stress Hormones
While high-intensity exercise can be great for cardiovascular fitness, it can also elevate levels of cortisol, the body’s primary stress hormone. Chronically high cortisol levels encourage fat storage, particularly around the middle, and can disrupt metabolism. When combined with poor nutrition or inadequate recovery, this can make weight loss even more challenging.

Strenuous Exercise Can Increase Appetite
High-intensity workouts can increase hunger levels, leading to overeating post-workout. Studies show that people tend to overestimate the amount of energy they have burned and compensate by eating more — often reaching for processed, high-sugar, or high-fat foods that hinder progress. Refuelling with the right nutrients is key to preventing this.

Exercise May Slow Metabolism
Over-exercising whilst undereating can lead to a slowed metabolism as the body conserves energy in response to perceived starvation. This survival mechanism can result in fat retention rather than fat loss, making long-term weight loss more difficult.

The Role of Hormones
Hormones play a crucial role in weight management — not just sex hormones but also insulin, cortisol, and those that regulate hunger. Poor diet choices, stress, and inadequate sleep can lead to blood sugar spikes, insulin resistance, and hormonal imbalances that promote fat storage. Exercise alone does not address these underlying issues, whereas good nutrition can regulate hormones and support fat loss.

The Bottom Line: It’s All About What You Eat
Weight gain is largely driven by excessive consumption of the wrong foods. It is too much food — or too much of the wrong type of food —that leads to weight gain, not a lack of exercise. Exercise is however a great strategy for maintaining weight loss.

The Best Strategy for Weight Loss is:

• A Nutrient-Dense Diet: Eat whole, real foods, including protein, healthy fats, fibre-rich vegetables, and low-sugar fruits and don’t forget about your gut health.

• How and When You Eat: Meal timing and mindful eating can be game changers.

• Lifestyle Factors: Ensuring quality sleep and managing stress are essential for metabolic balance.

• Strength Training: Building muscle mass helps increase your metabolic rate and improve your strength and body composition.

I’ve worked with so many people who were surprised at how changing their diet and quite often eating more, allowed them to lose weight steadily and sustainably.

STOP focusing on doing more exercise, calorie counting and yo-yo dieting and START losing weight in a healthy, sustainable way.

If you want to learn how to lose weight for life, I’m here to help you.😉