The keto diet: what it is and what a 1-day keto menu actually looks like

The ketogenic diet is not a fad. It is a metabolic state in which the body runs on fat and ketone bodies rather than carbohydrate. Clinically we use it to lower insulin, treat epilepsy, drive metabolic remission and support weight loss – but only when it is timely for the person and built correctly.

What “keto” actually means

A ketogenic diet drives the liver to produce ketone bodies (mainly β-hydroxybutyrate) in response to drastic carbohydrate restriction. In practice this means:

• Carbohydrate: 20–50 g a day (net, fiber excluded)
• Protein: 1.2–1.7 g/kg body weight – enough to preserve muscle, not enough to drive gluconeogenesis
• Fat: the remainder of energy, preferably from mono-unsaturated and saturated sources, not industrial seed oils

That distribution moves most healthy adults into nutritional ketosis within 3–7 days (blood β-hydroxybutyrate 0.5–3.0 mmol/L). The first week’s “keto flu” is common: the body is switching fuel, electrolytes are lost more actively with urine, and fatigue, headache or nausea can appear before a new steady state settles in.

Which patients I put on keto

Three clinical indications have high-quality evidence:

• Type 2 diabetes remission (Hallberg et al., Diabetes Ther 2018) – at 1 year, 60% of patients reached HbA1c < 6.5% without medication
• Metabolic syndrome (Volek et al., Prog Cardiovasc Dis 2018) – meaningful drops in triglycerides, visceral fat and insulin
• Drug-resistant epilepsy in children (a classic indication since the 1920s)

For weight loss, keto works well short-term but at matched calorie deficits does not clearly outperform low-fat over the long run (Bueno et al., Br J Nutr 2013). Its edge appears when a person has strong appetite or hyperinsulinaemia – keto often blunts hunger more than a low-fat diet.

Who keto is NOT for

I would not recommend it without consultation for type 1 diabetics (ketoacidosis risk without an endocrinologist), pregnant or breastfeeding women, rare inborn errors of fatty-acid oxidation, active eating disorders, advanced liver or kidney disease, and several psychiatric conditions. That is precisely why keto belongs in a medical plan rather than an Instagram plan.

A 1-day keto menu with a clinical lens

This is a day I use frequently for onboarding patients. Total ≈1900 kcal (adjust to your requirement), carbs ≈28 g net, protein ≈110 g, fat ≈155 g. One-day sample – full week, recipes and shopping list are on the /keto page.

Breakfast · 8:00

• 3-egg omelette in butter with spinach and feta
• ½ avocado
• Black coffee or green tea (no milk, no sugar)
• ≈ 480 kcal · 4 g carbs · 27 g protein · 38 g fat

Lunch · 13:00

• Grilled salmon (180 g) with lemon
• Large salad: rocket, cucumber, radish, olives, mozzarella, extra-virgin olive oil
• 1 tbsp pumpkin seeds
• ≈ 620 kcal · 8 g carbs · 42 g protein · 47 g fat