Ketogenic Diet

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Pie charts showing the composition of various nutritional concepts:
typical western diet (corresponds to the DGE recommendation with approx. 50% carbohydrate content); the Atkins diet in its introductory phase; Ketogenic diet with 4: 1 ratio of fat to carbohydrates / protein ; Medium-chain triglycerides (MCT) ketogenic diet

The ketogenic diet is a carbohydrate-limited, protein and energy-balanced and therefore high-fat form of dietary nutrition that mimics the starvation metabolism in certain aspects. With this form of nutrition, the body no longer draws its energy requirements from fat and glucose , but only from fat and the eponymous ketone bodies built up in the body , which serve as substitutes for glucose. A ketogenic diet is used as a therapeutic method especially in children with drug-resistant epilepsy , glucose transport disorders ( e.g. GLUT1 deficit syndrome ) and pyruvate dehydrogenase deficiency . More recent research results also suggest that therapy for Alzheimer's disease appears possible. In this context, it must be calculated individually and monitored by a doctor. Ketogenic forms of nutrition are now increasingly practiced by healthy people in a non-medical form, for example to reduce excess weight , by athletes, or as part of other low-carb diets such as the Atkins diet .

effect

Proteins can be converted to approx. 50% in the metabolism and fats due to their low glycerine content only approx. 10% to glucose in order to maintain the blood sugar level and thus above all to supply the brain with energy. When hungry, the body first draws on its glycogen stores (the storage form of carbohydrates in the liver) and then increasingly switches to a starvation metabolism. This type of metabolism is characterized, among other things, by the fact that the fatty acids from food are broken down in the liver to form ketone bodies , which, instead of glucose , are supposed to efficiently meet the energy requirement, especially the energy requirement of the brain , in an alternative way. This desired metabolic state is called ketosis .

Indications

In addition to patients with a glucose transport disorder or a pyruvate dehydrogenase deficiency , the use of the ketogenic diet can be considered in patients with epilepsy , for whom more than two anticonvulsant drugs have not had sufficient effect and for whom epilepsy surgery is not an option . It can be used for different types of seizures, causes of epilepsy and in age ranges up to adolescence, but seems to lose effectiveness beyond the 8th to 12th year of life and is more difficult to carry out. In infants less than one year it is equally applicable to that in children beyond the first year. There is good individual case experience with the treatment of Rett syndrome , Landau-Kleffner syndrome and Ohtahara syndrome .

After potassium bromide (1857) and phenobarbital (1910), the ketogenic diet was first introduced specifically in 1921 as the third anticonvulsant therapy option at that time . It had been observed that starvation had a beneficial effect on the seizure situation in many epilepsy patients, and attempts were made to combine the state of carbohydrate deficiency during starvation with sufficient fat and protein intake.

Alzheimer's disease is viewed in recent studies as a possible special form of glucose deficiency in the brain. The sharp reduction in carbohydrates improves the cells' insulin sensitivity, not only in the peripheral areas of the body, but also in the central nervous system. This resulted in a positive effect, at least in animal experiments on mice.

Calculation, implementation

For a ketogenic diet, the energy requirement (approx. 80–320 kJ / kg = 20–80 kcal / kg depending on age and energy expenditure) and the protein requirement (0.7–2 g / kg depending on age) are calculated and then the " ketogenic ratio ”(typically 3–4.5: 1). The ketogenic ratio determines the mass ratio of fat to carbohydrates + proteins. For example, a ketogenic ratio of 4: 1 means that 80% of the mass of the food must consist of fats. In the remaining 20% ​​of the food mass, a protein mass covering the requirement must be accommodated. Accordingly, carbohydrates should only be consumed in minimal amounts in order to maintain effective ketosis . A ketosis caused by an arbitrarily induced carbohydrate deficiency is broken within a short time by the intake of small excess amounts of carbohydrate, which can lead to increased seizures again. This strict diet regimen requires careful determination of the indications , some detailed knowledge and close cooperation between the treatment team and the patient, their caregivers (e.g. parents) and their social environment. The doctor must repeatedly adjust the diet prescription to the course and the needs that can be identified from it. The proper implementation of the diet must be monitored via urine and / or blood ketosis (similar to blood sugar monitoring in diabetics ).

MCT Based Ketogenic Diet

A glass bottle of 250 ml of Liquigen, a white opaque liquid
An emulsion of medium chain triglycerides

In the 1960s it was discovered that, medium chain triglycerides (engl .: medium chain triglycerides (MCT)) more ketone bodies and thus more energy per unit mass-produce in the body as the predominantly long chain triglycerides normal food fats. MCTs are also absorbed more efficiently and transported to the liver more quickly via the portal vein rather than the lymphatic system . The advantage for patients on a ketogenic diet is the possibility of increasing the mass fraction of carbohydrates a little in order to be able to use better-tasting and therefore better-accepted dishes. However, gastric and intestinal problems are sometimes reported. In some American clinics, the MCT diet replaces the classic ketogenic diet, although some use a mixture of both.

Risks

A ketogenic diet harbors various risks: The relatively high protein and fat content increases the risk of cardiovascular diseases . In addition, a ketogenic diet can also lead to an unbalanced vitamin balance, as fruits and vegetables are rarely consumed due to their often high carbohydrate content. So that the patient does not suffer any permanent health damage due to a ketogenic diet, it should therefore only be carried out under medical supervision.

Side effects

Temporary side effects are mainly digestive and bowel problems . Furthermore, tiredness is sometimes increased , especially in the first two weeks of the metabolic change, while this is often followed by better alertness . In addition, there are: refusal of food or hunger and related psychological problems, hypercholesterolemia (conclusive long-term studies on this side effect do not exist, but a ketogenic diet is not to be equated with a "fat fattening", since the energy supply is limited). Overall, the side effect profile is somewhat more favorable than with intensive pharmacological anti- convulsive therapy.

Ketogenic diet for the therapy of epilepsy patients

The ketogenic diet is a recognized form of therapy for drug-resistant epilepsies in childhood and various rare metabolic disorders, in particular carbohydrate metabolism disorders.

According to a study by the Johns Hopkins Children's Center that included 101 epilepsy patients between the ages of 2 and 26 who followed a ketogenic diet, these suffered fewer or no more uncontrolled seizures. After a 16-month to 8-year ketogenic diet, no health damage induced by this diet could be demonstrated in these patients. Ketone bodies are more energetic and burn more slowly than glucose from carbohydrates. If the cause of the epilepsy attack is hypoglycaemia in the brain, this occurs more slowly in ketone bodies before it is naturally compensated, which means that the attack can stop.

literature

  • FAM Baumeister: Ketogenic Diet - Diet as a Therapy Strategy. SPS-Verlagsgesellschaft, Heilbronn 2004, ISBN 3-936145-19-9 .
  • John M. Freeman, Jennifer B. Freeman, Millicent T. Kelly: The ketogenic diet. A treatment for epilepsy. 3rd ed. Demos, New York 2000, ISBN 1-888799-39-0 .

Web links

Individual evidence

  1. ↑ a b PR Huttenlocher, AJ Wilbourn, JM Signore: Medium-chain triglycerides as a therapy for intractable childhood epilepsy. In: Neurology. Hagerstown Md 21.1971, 11 (Nov), 1097-1103. PMID 5166216 ISSN  0028-3878
  2. ^ Suzanne M. de la Monte, Jack R. Wands: Alzheimer's Disease Is Type 3 Diabetes Evidence Reviewed . In: Journal of diabetes science and technology (online) . tape 2 , no. 6 , December 3, 2016, p. 1101-1113 , PMID 19885299 , PMC 2769828 (free full text).
  3. ↑ EG Neal, H Chaffe, RH Schwartz, MS Lawson, N Edwards a. a .: The ketogenic diet for the treatment of childhood epilepsy, a randomized controlled trial. In: The Lancet Neurology . 2008, 7: 500-506. doi: 10.1016 / S1474-4422 (08) 70092-9 . PMID 18456557 ISSN  1474-4422
  4. ↑ JW. Wheless: History and origin of the ketogenic diet . (PDF; 3.7 MB) In: Carl Ernest Stafstrom, Jong M Rho: Epilepsy and the ketogenic diet. Humana Press, Totowa 2004, ISBN 1-58829-295-9 .
  5. ↑ Ketogenic Diet - Risks. June 9, 2016, accessed February 20, 2018 .
  6. ↑ “ Ketogenic Diet - A Challenge for Patients and Professionals. ”In: Nutrition review 8/17. UMSCHAU ZEITSCHRIFTENVERLAG GmbH: A company of the ACM Group, August 15, 2018, accessed on March 31, 2019 .
  7. ^ " Despite its temporary side effects, we have always suspected that the ketogenic diet is relatively safe long term, and we now have proof. In: High-Fat Ketogenic Diet to Control Seizures Is Safe Over Long Term, Study Suggests. In: SienceDaily.com. Johns Hopkins Medical Institutions, February 17, 2010, accessed March 4, 2011 .
  8. ↑ Christian Floto , Michael Ristow : Low-Carb - Less carbohydrates, better health? Deutschlandfunk - “Consultation hour”, 6 September 2016