A high protein diet is characterized by prioritizing your intake of foods that are rich in protein (like meat and eggs), and reducing your intake of high-carb foods (like bread or pasta). Eating more protein helps to reduce hunger and help to keep it full, as protein has a direct effect on ghrelin and other hormones that regulate appetite.

In this way, proteins can increase metabolism, helping to burn more calories, and the absence of carbohydrates in the diet would cause the body to use other sources of fat to produce energy.

It is normal to feel a little weak and dizzy within the first days of starting the diet. These symptoms usually resolve within 3 or 4 days, which is the time needed for the body to get used to a reduction in carbohydrates. You can also opt for a low carb diet to help you gradually reduce carbohydrates before starting the high protein diet. Read more about the low carb diet and what it entails.

What to eat

The foods you should eat in a high protein diet include:

Low-fat cuts of poultry and derivatives, like chicken breast, turkey breast and eggs
Lean cuts of red meat
Fish, like sardines, tuna and salmon
Low-fat dairy products and derivatives, such as skimmed cow's milk, white or low-fat cheeses, skimmed yogurt
Plant-based drinks, such as almond milk;
Vegetables, such as chard, kale, spinach, lettuce, arugula, watercress, chicory, carrots, cabbage, tomatoes, cucumbers, radishes, eggplant, Brussels sprouts, broccoli, cauliflower, artichokes, onions, garlic, paprika and asparagus
Beans, such as red beans, chickpeas, corn, peas and soybeans
Oils, such as olive, sunflower, corn or linseed oil
Nuts, such as peanuts, chestnuts, almonds, hazelnuts and Brazil nuts
Seeds, such as chia, flaxseed, sesame, pumpkin and sunflower
Other foods, such as avocado, olives and lemon

A high protein diet can be followed for 15 days with a 3-day break, and can be repeated for a maximum of another 15 days.

Foods to reduce

Foods that you should reduce intake of or eliminate are:

Whire grains, such as pasta, rice and flour
Tubers, such as potatoes, sweet potatoes and cassava;
Sugar, and foods that contain it, such as cookies, sweets, cakes, soft drinks, honey and processed juices;
Alcohol, such as beer, whiskey and wine.

It is important to avoid consuming these foods when maintaining a high protein diet to avoid changes in metabolism that cause the body to stop using protein and fat as an energy source. Check-out a list of high carb foods that you should also avoid consuming.

One week meal plan

Check-out a week long sample meal plan that outlines how you can organize your meals when maintaining a high protein diet:

	Breakfast	Lunch	Snack	Dinner
Monday	Skim milk with avocado and scrambled eggs with onion and paprika	Boiled fish with spinach, seasoned with lemon juice	1 skim yogurt with peanut butter	Tuna and lettuce salad, seasoned with yogurt sauce, coriander and lemon
Tuesday	Skim yogurt with flaxseed, one cheese ball and cold-cut turkey breast slice	Grilled chicken with cucumber, lettuce, pea, tomato salad, seasoned with olive oil and lemon	Boiled egg and carrot sticks	Grilled salmon with broccoli, carrot and tomato salad, seasoned with lemon and flaxseed oil
Wednesday	Coffee with skim milk and one boiled egg	Omelet with ham and cheese, and arugula salad seasoned with olive oil and lemon	Skim yogurt with chia seeds and 2 slices of cheese	Spaghetti squash with minced meat and homemade tomato sauce
Thursday	Avocado smoothie made with skim milk	Grilled tuna with chards, seasoned with flaxseed oil	Lemon juice, one boiled egg and a slice of cold-cut turkey breast	Grilled turkey breast with tomato and grated cheese with olive oil, with arugula, chick pea and carrot salad seasoned with lemon
Friday	Skim yogurt and scrambled egg with chards and cheese	Eggplant stuffed with pulled chicken breast (sauteed with paprika, and onion), baked in the oven with grated cheese	Avocado smoothie with almond milk	Omelet with spinach, black-eyed peas and onion
Saturday	Skim milk with 2 cheese balls and ham	Salad with lettuce, arugula, cucumber and avocado, with chopped avocado and boiled egg, seasoned with yogurt dressing, parsley and lemon	3 walnuts and one skim yogurt	Cream of carrots with pieces of white cheese and coriander
Sunday	Coffee with almond milk and omelet with ham and cheese	Grilled beef with asparagus sauteed with olive oil	Avocado slies with peanut butter	Smoked salmon salad with white and purple lettuce, chopped avocado, chia seeds and walnuts, seasoned with olive oil and lemon

The quantities of foods in this meal plan will vary according to age, sex, physical activity and health history. Therefore, it is important to consult a registered dietitian for a more complete assessment to calculate proportions and serving sizes.

Other considerations

Before starting any diet, it is important to consult your doctor or a registered dietitian to ensure the diet will not be harmful.

The high protein diet should only be followed for a maximum of 1 month, after which it is possible to maintain a low-carb diet to maintain weight and ensure adequate intake of all nutrients.

If you are vegetarian, there are foods that are rich in vegetable proteins, such as beans, chickpeas and quinoa, for example.

Contraindications to remember

The high protein diet should not be followed by patients with kidney problems, as consuming large amounts of protein can cause even more damage to the kidneys. Furthermore, it should not be followed by children, pregnant women, nursing women, or people with eating disorders.

Maintaining a high-protein diet for a long time can have metabolic consequences in several organs, and can lead to abnormalities in water-electrolyte levels, acid-base metabolism, bone metabolism, renal function and endocrine function.