How to actually lose weight, and what to do first

The most asked question is "what should I eat to get lean", which is hard to answer because it is not quite the right question. The more useful one is "what could I still be doing in six months".

What is the first thing to do?

Find out what you are actually eating now, before cutting anything. Studies repeatedly find that people underestimate their intake substantially, and someone saying "I barely eat and still don't lose" is usually in this situation without knowing it.

Weigh and record honestly for three or four days. Not forever — just long enough to recalibrate your eye once. That single exercise changes everything that comes after it.

How much should you aim to lose a week?

0.5 to 1% of body weight per week. For someone at 80 kg that is roughly 0.4 to 0.8 kg a week, which comes from eating about 300 to 500 calories a day less than you burn.

Can you go faster? Yes, at a price. Garthe and colleagues (2011) found that athletes losing more slowly, at 0.7% a week, held on to lean mass and even gained some, while a faster group at 1.4% did not. Weight that disappears quickly is not all fat.

Which diet is best?

The clearest answer comes from DIETFITS (Gardner 2018), which followed 609 people for 12 months comparing low-carbohydrate with low-fat. The results were 6.0 kg and 5.3 kg respectively — not a meaningful difference. More striking still, neither genotype nor insulin response predicted who should use which.

But the most important number in that study is not the average. Within each group there were people who lost more than 20 kg and people who gained. The variation is in the person, not in the diet.

Why does it slow down after a while?

Three things happen at once. A lighter body costs less to run. Non-exercise movement falls on its own without you noticing — you walk more slowly and fidget less. And portions creep back up once careful tracking stops.

The fix is not to cut food further as a first move. It is to check those three.

What do people who succeed have in common?

• Enough protein — around 1.6 grams per kilogram of body weight, which keeps you full and protects muscle.
• Resistance training — the signal that tells the body muscle is still needed while energy is short.
• Enough sleep — short sleep tilts what you lose toward lean tissue and makes you hungrier.
• Regular weighing, read as an average — not to judge yourself, but to see the direction before it is too late to act on.
• A plan for the days that go wrong — the people who last are not the ones who never slip, they are the ones who are back on track the next day.