Healthy weight loss: what works and what does not

What is a safe rate of weight loss?

A safe rate is one you can maintain while eating enough, without constant hunger or loss of strength. There is no single figure that works for everyone. The Spanish obesity guideline calls for setting realistic goals and reviewing them in the short, medium and long term [1]. It also notes that weight loss is not, by itself, the first priority of treatment [1].

If seeing changes means going hungry, missing meals with friends or constantly thinking about the scales, the pace is too demanding for you. In a consultation, we agree on goals that can be reviewed. Some weeks there may be no visible changes, and that does not mean the process has failed.

Eating 800 kcal a day or less is a treatment option, but only with medical supervision and as part of a programme involving several professionals [1]. It is not a shortcut to try on your own.

A weight-loss plan that works is one you can return to without guilt when the week gets complicated.

How to eat a little less without counting calories

To lose fat, you need to eat a little less than you expend. This is called a moderate calorie deficit. You can create one with slightly smaller portions and meals with fewer calories per bite, such as dishes with more vegetables and less added fat. This is the main component of any weight-loss eating plan [1].

You do not need to weigh everything. Start by organising the foods and meals you repeat most often. One example for lunch: half a plate of vegetables, a quarter of protein such as fish, eggs or pulses, and a quarter of bread, potatoes, rice or pasta. Adjust the amount to your hunger and activity level.

Before changing ten things, observe a typical week. When do you eat in the biggest rush? Which meals keep you satisfied, and which leave you picking at food without enjoying it? What groceries go unused? Your answers often point to the adjustment that would suit you.

It also helps to distinguish hunger from habit, tiredness or wanting to switch off. Aim for most meals to satisfy you and help you get to the next one without urgency, without banning foods.

Counting calories may help some people for a while, but it is not a requirement or a test of willpower. If tracking makes you anxious or rigid, stop and find another way to organise your meals.

How to manage when eating out or short on time

For a set lunch menu, choose a vegetable-based starter and a protein-based main, followed by fruit or coffee. If you fancy bread, include it as part of the meal. When time is short, tinned pulses, frozen vegetables, eggs and wholemeal bread can make a complete meal in ten minutes.

How can you preserve muscle while losing fat?

Weight loss does not always mean losing only fat. To preserve muscle, you need to eat enough, include protein at each meal and do strength training. The Spanish obesity guideline recommends strength training two or three times a week for adults with obesity who want to lose fat and maintain muscle mass [1].

You do not need to start intensely. You could learn the technique with supervision or use machines, resistance bands or your own body weight. Two short sessions a week with squats, wall push-ups and band rows are a good start. If you have pain, an injury or a medical condition, are pregnant, or have not exercised for a long time, adapt the plan with the relevant healthcare professional.

Strength also matters outside the gym. You may feel steadier when standing up, carry your shopping with less effort or climb a hill you used to avoid. Starting small and repeating it helps you maintain the habit more than an intense programme you abandon after two weeks.

What mistakes do we see in consultations?

• Starting on Monday and changing everything at once. A new menu, daily gym sessions and no snacks are hard to maintain for more than a few days. One change you keep up is worth more than five you abandon.
• Looking only at the scales. Weight changes for many reasons and does not tell the whole story. We also look at habits, strength, hunger, sleep, tests when appropriate and how you feel.
• Cutting out bread, pasta or rice altogether. This can make eating out and sharing meals harder, and the plan becomes harder to maintain. Adjusting portions lets you keep eating them.
• Copying someone else’s menu. Their schedule, work and hunger are not yours. It is usually more useful to adjust what you already eat.

When to ask for help and whom to contact

Ask a dietitian for help if you have tried many plans without finding one that suits you, or if you want to lose fat without sacrificing muscle. You can also ask for help adapting your diet to a medical condition. Our weight-loss nutrition consultation explains how we work.

Do not copy a generic plan from the internet if you have kidney disease, are pregnant or breastfeeding, or have had an eating disorder. The same applies if you have diabetes and use insulin or medicines that can lower your blood sugar too much. If you are breastfeeding, avoid restrictive diets. If you have kidney disease, your nephrologist or dietitian will advise how much protein, potassium, phosphorus and other ions and minerals are right for you at your stage of disease. Our weight-loss diet guide provides general information. In these situations, we also coordinate changes with the healthcare professional managing your care.

Seek specialist help if weight and food take up a large part of your day. Also seek help if you hide food, keep eliminating more foods, feel out of control or compensate for what you eat.

The UK reference guideline recommends prompt referral to a specialist service when an eating disorder is suspected [2]. There is no need to wait until the situation seems severe.