KETO DIET: LEANER AND FITTER BODY THROUGH KETOSE

The ketogenic diet is largely based on avoiding carbohydrates, with energy supplied mainly by the other two macronutrients, fat and protein. But what is behind this hype? It is believed that the keto diet supports weight loss, inhibits inflammation, improves energy levels, and inhibits the growth of cancer cells. The reduced insulin secretion also has a positive effect on stable blood sugar and can reduce the risk of type 2 diabetes.

What is meant by the ketogenic diet?

In this diet, very few carbohydrates are consumed. With a few exceptions, foods in the keto diet should not contain more than 10g of carbohydrates per 100g. Sugar is completely forbidden. Which foods exactly belong to this diet and which do not are described in more detail below. Mainly, grains, sweets, and starchy foods such as potatoes are omitted. 

No more than 30-40g of net carbohydrates should be consumed per day. These come primarily from vegetables or berries. For this, sufficient protein should be consumed, and fat serves as the main energy source. Thus, 75-85% of the daily calorie intake is derived from fatty acids¹.

What happens in the metabolism when we eat carbohydrates?

When we eat carbohydrates , they are broken down into simple sugars in the intestine, because they can ultimately only be absorbed into the bloodstream in this form. Of course, our intestinal mucosa also absorbs direct sugar, which can be found in sweets or sodas, for example. In this liquid form, absorption happens fastest; the slowest absorption occurs with more complex carbohydrates, for example from whole grain rice and vegetables. When the sugar then enters the blood, it supplies the cells with energy. The excess sugar is stored in our muscle and liver cells. The signal for this storage process is given by the hormone insulin. Here you can find more detailed explanations about blood sugar.

However, the carbohydrate or sugar stores in our body are limited, and when they are already full, the excess sugar is converted into fat by our liver and stored in the cells. Unlike sugar stores, fat stores can be expanded almost indefinitely.

How does ketosis occur?

If no or almost no carbohydrates are taken in through food, after a while, the body begins to break down the carbohydrate stores from the liver and use them, for example, as an energy source for nerve cells and the brain. The glycogen stores in the muscles are then slowly emptied. This ensures that there is always a certain sugar level in the bloodstream to ensure energy supply³. 

Since these sugar stores are exhausted without their replenishment through food, the liver first begins to convert amino acids (the broken-down form of proteins) into carbohydrates³. However, only one-third of the amino acids in the body are actually available for this. The rest is needed for other processes. Stored fat, however, contains eleven times the calorie amount. In people with a higher body fat percentage, these stores are even significantly higher. Thus, it only makes sense for the body to now use these fatty acids as a carbohydrate replacement:

During the now occurring ketosis , the liver converts fats into so-called ketone bodies . Although they cannot be transformed into the actually required sugar, they fulfill the same functions in energy metabolism. They are thus virtually a substitute product for carbohydrates. Our energy system thus works like a hybrid vehicle: When the electric battery is empty, it switches to gasoline, our electricity being the carbohydrates and the gasoline then the ketone bodies⁴.

This ketogenic state is not dangerous or unhealthy. The process is completely natural and was a survival mechanism in prehistoric times, because back then there were no filled shelves in the supermarket. People often had hardly any carbohydrates available at times and simply had to manage without them. However, it can happen that in the first days of the transition, short-term side effects occur: headaches, fatigue, and sugar cravings are typical signs that the body is in the transition phase. However, these signs disappear after a few days and are usually due to sugar withdrawal.

Ketogenic Foods

• Animal Protein: fish, meat, eggs, e.g., salmon, mackerel, tuna, seafood, sea bream, ground beef, boiled beef, chicken, turkey, bresaola, bacon, game, collagen, whey protein, bone broth, gelatin, etc.
• Natural Fats: butter, ghee, coconut oil, MCT oil, extra virgin olive oil, cold-pressed sunflower oil, linseed oil, 100% nut and seed meal, avocado, etc.
• Grains and Nuts (also belong to fats): sesame, flaxseed, chia seeds, walnuts, hazelnuts, pumpkin seeds, sunflower seeds, pecans, almonds, coconut, etc.
• Dairy Products: cheese, yogurt, kefir, butter, milk, cream, sour cream, buttermilk, quark, cottage cheese, etc.
• Low-Sugar Drinks: coffee, bulletproof coffee (with butter, MCT oil, and collagen), infused water, unsweetened tea, sugar-free amino acids and protein shakes, etc.
• Low-Carbohydrate Vegetables: lettuce, cucumber, spinach, asparagus, zucchini, broccoli, cauliflower, green beans, artichoke, eggplant, onion, spring onion, leek, mushrooms, bell pepper, Brussels sprouts, olives, chili, etc.
• Low-Sugar Fruit: berries, e.g., blueberry, blackberry, raspberry, strawberry, blackcurrant, blackcurrant, lemon, lime, etc.
• Flour Alternatives for Cooking and Baking: almond flour, locust bean flour, linseed flour, coconut flour, walnut flour, etc.
• Sugar Alternatives/Natural Sweeteners: stevia, erythritol, xylitol, etc.

Donts: These Products and Foods Are Not on the Keto Diet 

Since it is primarily about avoiding carbohydrates, grains, sugar, potatoes, soft drinks, juice, most fruits, and also high-carbohydrate vegetables should be omitted in the keto diet. The following examples are in no case on the keto meal plan:

• Grain Products: pasta, rice, bread, wheat, rye, spelt, barley, corn, potato, sweet potato, chips, rice cakes, crackers, muesli, cornflakes, oatmeal, pizza, etc.
• Legumes: chickpeas, peanuts, lentils, beans, soy, etc.
• Sugary Foods: chocolate, sweets, sweetened dairy products such as fruit yogurt, jam, maple syrup, honey, table sugar, fructose (agave), coconut blossom nectar, ready-made products containing sugar, pancakes, cake, etc.
• High-Carbohydrate Vegetables: pumpkin, carrot, and other root vegetables
• High-Sugar Drinks: fruit juices, fruit smoothies, soft drinks e.g., cola, Fanta, Sprite, energy drinks, etc.
• High-Sugar Fruit: banana, apple, melon, cherries, peach, nectarine, pear, date, mango, apricot, pineapple, orange, mandarin, papaya, etc.

Distinction from the Paleo Diet

The previous article was about the Paleo Diet, which has some parallels to the Keto Diet : In the Paleo Diet , few carbohydrates are consumed, grains are forbidden, and protein and fat are the focus. However, dairy products are not allowed in the Paleo diet, while various sugary fruits, little honey, and some starchy foods such as sweet potatoes are in a gray area. In the ketogenic diet , some root vegetables such as carrots are avoided because they contain more carbohydrates , which is not the case in the Stone Age or primitive diet.

What Benefits Does the Ketogenic Diet Have?

Primarily, the blood sugar is kept low and stable, which has many health and aesthetic benefits:
Less insulin is released, allowing the pancreas to recover and reducing the risk of type 2 diabetes. A stable blood sugar level results in fewer cravings, which means less excess energy is stored in fat cells. This makes the keto diet a way to lose weight without starving or counting calories. The more stable blood sugar also improves energy levels and concentration⁵.

Because many potential allergens such as gluten and soy are automatically avoided, the intestinal mucosa can recover. This leads to less inflammation in the digestive tract and throughout the body. Avoiding sugar can improve the oral flora and the ratio of microorganisms in the mouth and throat, which prevents cavities and other oral diseases. There are also numerous studies on cancer and the ketogenic diet that support this form of nutrition. Cancer cells feed on sugar, which is why it is not very beneficial if the body has enough or too much of it available.

Caution with the Ketogenic Diet – For Whom Is It Not Recommended?

For people who are intolerant to dairy products, not all Keto Products are suitable. However, this should not be completely exclusionary, as there are still plenty of other foods that can be consumed. It could still be a bit more complicated for vegans. They should be careful with the keto diet and speak to a doctor about possible supplementation of micronutrients and essential amino acids.

Athletes with a high muscle mass and little body fat are usually advised against the ketogenic diet : Their carbohydrate stores are larger than those of an average person and are regularly emptied during intense training sessions. Approaching energy supply through ketosis indirectly is less sensible. To consume enough proper nutrients for muscle building or maintenance, they would have to consume extremely high amounts of animal protein, which could potentially strain the kidneys and is also questionable from an ecological and ethical standpoint.

Conclusion on the Keto Diet:

The ketogenic diet can have many benefits for health and a lean body. However, like any diet, it is not optimal for everyone and may need to be adapted slightly.

¹ DRKS (2017): Influence of an energy-balanced ketogenic diet (KD) - a highly carbohydrate-reduced and fat-rich diet - on the physical endurance performance of healthy adults
[https://www.viomedo.de/klinische-studien/6038/einfluss-energiebilanzierten-ketogenen-diaet-kd-stark-kohlenhydratreduzierten-fettreichen-kostform-koerperliche-ausdauerleistungsfaehigkeit-gesunden-erwachsenen; 25.07.2020].

² Simply Keto: What is the ketogenic diet? [https://simplyketo.de/was-ist-keto; 25.07.2020].

³ Martin, Hans Helmut (2014): Full energy while fasting. UGB forum special. S 10-14.

⁴ Bracht, Dr. Med. Petra (2018): Intermittent fasting – For a long life – lean and healthy.

⁵ Medizindoc (2020): Study: How a ketogenic diet works best – Pros and cons of a ketogenic diet. [https://medizindoc.de/studie-eine-ketogene-diaet-funktioniert-am-besten-in-kleinen-dosen-finden-wissenschaftler-der-yale-university; 26.07.2020].