What is Ketosis and Why Does it Work? A Plain Explanation

By Augustine, Founder of The Larder

Most people have heard the word ketosis.

Very few understand what it actually means — or why it works so reliably when everything else has failed.

This is not a complicated idea, but it is a powerful one and once you understand it, the way you think about food, hunger, and energy will never be quite the same.

What is ketosis?

Ketosis is a metabolic state where your body uses fat — rather than glucose — as its primary fuel.

That's it. That's the whole idea.

Your body is capable of running on two different fuel systems. The first runs on glucose, which comes from carbohydrates. The second runs on fat and ketone bodies, which your liver produces when carbohydrate intake is very low.

Most people in the modern world run exclusively on glucose. They eat carbohydrates, blood sugar rises, insulin is released to clear the glucose, energy arrives briefly, then crashes. Hunger returns. They eat again. The cycle repeats — every few hours, all day, every day.

Ketosis breaks that cycle entirely.

Why does it work?

When carbohydrate intake is very low, blood sugar stops rising and falling. Insulin levels drop and stay low. And when insulin is low, something remarkable happens — your body stops storing fat and starts burning it.

Stored body fat, which was previously locked away by chronically elevated insulin, becomes accessible as fuel. Your liver converts fatty acids into ketone bodies. Your cells — including your brain — begin running on ketones instead of glucose.

The results of this shift are consistent and well-documented:

Hunger drops. Not through willpower or restriction — but because your body is genuinely, adequately fuelled. Many people in ketosis eat one or two meals a day without effort, not because they are forcing themselves to fast, but because they simply are not hungry.

Energy stabilises. Without the blood sugar spikes and crashes of a glucose-based metabolism, energy becomes steady and predictable. No 3pm slump. No desperate reach for caffeine. Just consistent, reliable fuel throughout the day.

Weight releases. When insulin is low and stored fat is accessible as fuel, the body has no reason to hold onto excess weight. Many people lose weight in ketosis without tracking calories, without restriction, and without hunger — because the metabolic conditions that drove fat storage have been removed.

Mental clarity improves. Ketone bodies are a preferred fuel for the brain. Unlike glucose, they provide steady energy without spikes or crashes. Many people report significant improvements in focus, mood, and cognitive function within the first weeks of ketosis.

Why does this matter for your food?

Ketosis is not complicated to achieve. But it does require consistency.

To stay in ketosis, carbohydrate intake needs to remain very low — typically under 20- 25 grams per day. For most people, this means removing grains, sugars, starches, and most plant foods from their diet. What remains is meat, animal fats, eggs, high fat dairy like cheese and cream and some spices or herbs — foods that are naturally low in carbohydrates and high in the protein and fat your body actually needs.

The challenge is not understanding what to eat. The challenge is the practical reality of eating this way consistently when most of the food around you is designed to spike blood sugar and keep you hungry.

This is exactly why The Larder exists.

Every product we make is animal-based and low-carb by default. Any combination of our food will keep you in ketosis without tracking, measuring, or thinking about it. We have done the work so you don't have to.

What to expect when you start

The first three to seven days of ketosis are often the hardest. Your body is switching fuel systems — a process that takes time and can feel uncomfortable. You may experience fatigue, headaches, brain fog, or irritability- this feels like 'drug withdraw'. This is commonly called the keto flu, and it is temporary. But it feels awful, because thats what a drug sugar actually is - you have to detox it. 

What helps: drink enough water, make sure you are getting adequate sodium and electrolytes, and eat enough fat. Under-eating fat is one of the most common mistakes in early ketosis. Fat is your fuel now — don't restrict it.

By day seven to eleven, most people notice a shift. Energy begins to stabilise. Hunger drops. Mental clarity starts to return. By the end of the second week, many people feel better than they have in years.

How long does it take to become fat-adapted?

Getting into ketosis — measurable ketones in your blood — typically takes four to fourteen days of very low carbohydrate eating.

Becoming fully fat-adapted — where your body is running efficiently and comfortably on fat as its primary fuel — takes longer. Most people reach this point between four and twelve weeks. During this time, athletic performance may dip before it improves, energy may fluctuate, and digestion will adjust. This is normal. Give your body time.

The longer you stay in ketosis, the more efficient your fat metabolism becomes. Many people who have been fat-adapted for months or years describe it as a fundamentally different relationship with food — one where eating is simple, hunger is manageable, and energy is reliable.

Do I need to track macros or measure ketones?

No — and I would encourage most beginners not to start there.

Tracking and measuring adds friction, and friction breaks consistency. If you eat animal-based, low-carb food and avoid sugar, grains, almost all plants, and seed oils, you will be in ketosis. You do not need a blood meter or a macro spreadsheet to confirm it.

The most reliable signal is how you feel. Reduced hunger. Steady energy. Reduced body pain. Mental clarity. These are the signs that your body has switched fuel systems — and they are more meaningful than any number on a device.

A final note

Ketosis is not a diet trend. It is not a hack or a shortcut. It is a return to a metabolic state that humans have used for most of our evolutionary history — one that prioritises fat metabolism, stabilises blood sugar, and removes the constant demand to eat.

Your body already knows how to do this. It has been waiting for the right fuel.

— Augustine

Ready to start? Visit our Start page to find the right place to begin. Or join our WhatsApp community and ask Augustine directly.