Ketogenic Diet (Keto): Complete Guide to Safely Entering Ketosis

The ketogenic diet, or keto, relies on a drastic reduction in carbs in favor of fats to bring your body into ketosis—a metabolic state where the body burns fat as its primary energy source. Originally developed in the 1920s to treat epilepsy, it is now adopted for weight loss, mental clarity, and managing type 2 diabetes. FoodCraft supports you with tailored keto recipes, a macro calculator with a ketogenic preset, and AI planning that respects your macronutrient ratios.

Steps

1

Understand macronutrient ratios

The standard ketogenic diet (SKD) follows a distribution of about 70-75% fat, 20-25% protein, and 5-10% carbs, which is generally 20 to 50 g of net carbs per day. Use FoodCraft's macro calculator with the keto preset to determine your personalized goals based on your weight, height, age, and activity level.

2

Clear your pantry of high-carb foods

Remove temptations: bread, pasta, rice, cereal, sugar, candy, fruit juice, soda, and most fruits (except berries in small quantities). Replace them with keto-friendly foods: olive oil, butter, avocados, macadamia nuts, aged cheeses, and low-carb vegetables.

3

Create your keto food list

Your staples will be: fatty meats and fish (salmon, sardines, pork chops), eggs, cheeses (comté, brie, goat cheese), avocados, olive oil and coconut oil, butter, nuts (macadamia, Brazil nuts, almonds), leafy greens (spinach, arugula, kale), broccoli, cauliflower, zucchini, and mushrooms.

4

Manage the adaptation phase (keto flu)

During the first 2 to 7 days, you might experience fatigue, headaches, irritability, and cramps—this is the "keto flu". It's caused by the loss of water and electrolytes linked to the drop in carbs. Increase your intake of salt (bone broth, pink salt), magnesium (spinach, almonds), and potassium (avocado, mushrooms).

5

Plan your keto meals with FoodCraft

FoodCraft's AI planning generates 7-day ketogenic menus while strictly respecting your macronutrient ratios. Each meal displays its net carbs, fats, and protein. The algorithm ensures enough variety to avoid food boredom while maintaining ketosis.

6

Monitor your state of ketosis

You can check your ketosis state with urine strips (simple but imprecise) or a blood ketone meter (more reliable). Natural signs of ketosis include reduced appetite, stable energy, and slightly fruity breath. FoodCraft displays each day's total net carbs to help you stay within the ketogenic range.

The science of ketosis

Normally, your body uses glucose (from carbs) as its primary fuel. When you drastically reduce carbs, your glycogen stores are depleted in 24 to 72 hours. The liver then begins to convert fatty acids into ketone bodies (acetoacetate, beta-hydroxybutyrate, and acetone), which become the alternative energy source for the brain and muscles. This metabolic state, called nutritional ketosis, is distinct from diabetic ketoacidosis (a pathological condition). Research shows that nutritional ketosis can improve insulin sensitivity, reduce blood triglycerides, and promote fat loss while preserving muscle mass.

What to eat and what to avoid on a ketogenic diet

Foods allowed on keto are high in fat and low in carbs: meats (beef, pork, poultry with skin), fatty fish (salmon, mackerel, sardines), whole eggs, aged cheeses, butter and heavy cream, oils (olive, coconut, avocado), avocados, nuts and seeds (in moderation), low-carb vegetables (spinach, cauliflower, broccoli, zucchini, asparagus), and berries (raspberries, blackberries, in small portions). Avoid: sugar in all forms, grains and their derivatives (bread, pasta, rice), legumes (too high in carbs for keto), potatoes, most fruits, low-fat products (often high in added sugar), and sugary alcohol.

Understanding and managing keto flu

The keto flu isn't a real flu but a set of transient symptoms: fatigue, headaches, nausea, dizziness, irritability, and muscle cramps. It typically occurs between the second and fifth day and rarely lasts more than a week. The main cause is the rapid loss of water and electrolytes: by reducing carbs, your kidneys excrete more sodium. The solution: increase your sodium intake (5 to 7 g per day, via salty broth), magnesium (400 mg per day, via supplements or rich foods), and potassium (via avocado and green vegetables). Stay well hydrated and don't cut your calorie intake too abruptly during this adaptation phase.

FoodCraft Tip

Delicious keto recipes on FoodCraft

FoodCraft offers keto-compatible recipes: chocolate fat bombs, cauliflower crust pizza, grilled salmon with lemon butter, and cacao avocado mousse. Each recipe displays its net carbs so you can stay in ketosis. Use the "keto" filter to access compatible recipes directly.

Macro calculator with ketogenic preset

FoodCraft's nutrition calculator includes a ketogenic preset that automatically calculates your optimal fat, protein, and carb ratios based on your profile. It adjusts your goals whether you're aiming for weight loss, maintenance, or muscle gain, while respecting the carb range necessary for ketosis.

Frequently Asked Questions

How long does it take to enter ketosis?
By keeping your carb intake under 20 to 50 g net per day, most people enter ketosis in 2 to 4 days. Certain factors speed up the process: intermittent fasting, physical activity, and good hydration. Indicator signs include decreased appetite, stable energy, and sometimes fruity-smelling breath.
Is the ketogenic diet dangerous for your health?
For most healthy adults, a short- to medium-term ketogenic diet (a few months) is considered safe. However, it is not recommended for people with pancreas, liver, or gallbladder diseases, pregnant or breastfeeding women, and people with a history of eating disorders. Consult your doctor before starting, especially if you take medication for diabetes or hypertension.
Can you consume alcohol on a keto diet?
Some alcoholic drinks are keto-compatible in moderate amounts: pure spirits (whiskey, vodka, gin—0 g carbs), dry wine (red or white, about 2 g carbs per glass). Avoid beer (high in carbs), sugary cocktails, and sweet wines. Note: in ketosis, your alcohol tolerance decreases significantly.
How do you avoid constipation on a ketogenic diet?
Constipation is a common keto side effect, linked to the reduction in fiber. To remedy it: consume fiber-rich, low-carb vegetables (broccoli, spinach, cauliflower), add chia or flax seeds to your meals, drink enough water (at least 2 liters per day), and ensure adequate magnesium intake. FoodCraft integrates these elements into its keto planning to ensure proper fiber intake.
Can you do intensive sports on a ketogenic diet?
Yes, but an adaptation period of 2 to 6 weeks is necessary. During this phase, your performance may temporarily drop. Endurance sports (running, cycling, swimming) adapt particularly well to keto once adaptation is complete. For explosive sports (weightlifting, sprinting, HIIT), some practice the Targeted Ketogenic Diet (TKD) by adding 20 to 50 g of carbs around their workout.

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