Ketose und Knochen?

[arena]

Wie sieht es eigentlich mit den Knochen aus in Keto?
dh Calcium ist da ja eher schwer zu bekommen, zudem wirkt Ketose ja sauer was das Calcium aus den Knochen zieht.
Wurde da schonmal geforscht oder ähnliches?

[ilpadre]

Auf die Schnelle habe ich nicht viele Studien zum Thema gefunden, aber hier ein paar:

Recenti Prog Med. 2002 Dec;93(12):671-5.

[Nutritional status and bone mineral mass in children treated with ketogenic diet]

[Article in Italian]

Bertoli S, Striuli L, Testolin G, Cardinali S, Veggiotti P, Salvatori GC, Tagliabue A.

Centro Internazionale per lo Studio della Composizione Corporea, Universita degli Sudi di Milano. simona.bertoli@unimi.it

Ketogenic diet (KD) is a high fat (90%), low carbohydrate (3%) diet used to treat refractory seizures in child. This highly unbalance diet could damage nutritional status. The aim of this study is to evaluate if KD can affect on growth and on mineral status in child. Seven child (1 females and 6 males) age between 3-16 years were retrospectively studied to assess nutritional status during KD; we evaluated anthropometric measurements (weight, height, skinfold and circumferences), bone mineral content and bone mineral density, using x-ray energy absorptiometry (DXA) and some biochemical parameters. We have not found any short term modifications (six months) concerning growth, and biochemical parameters studied. KD could worsen bone mineral status.

Med Sci Sports Exerc. 2000 Mar;32(3):690-4.

High-carbohydrate versus high-fat diets: effect on body composition in trained cyclists.

Brown RC, Cox CM, Goulding A.

Department of Human Nutrition, University of Otago, Dunedin, New Zealand. rachel.brown@stonebow.otago.ac.nz

PURPOSE: Recent research suggesting the benefits of high-fat diets for endurance athletes have been viewed with caution because of the potential negative health consequences, including increased adiposity. METHODS: We have examined the effects of a high-fat (HF, 50% of total energy from fat and 37% from carbohydrate) versus a high-carbohydrate (HC, 15% of total energy from fat and 69% from carbohydrate) diet on body fat, lean body mass, and bone mineral density (BMD) in 32 endurance-trained cyclists over a period of 3 months. Body composition was assessed by dual x-ray absorptiometry at baseline and after 3 months. RESULTS: Total and percent body fat, lean tissue mass, and body weight were not significantly different within and between each diet group from baseline to week 12. Total body BMD increased significantly within HF (P = 0.02), but nonsignificantly in HC, over the 12-wk period. CONCLUSIONS: In conclusion, during periods of endurance training when energy requirements are high, increasing the percentage of fat in the diet to approximately 50% of total energy does not increase body weight or adiposity because athletes are able to maintain energy balance.

Calcif Tissue Int. 1998 Jul;63(1):74-9.

Effects of high-fat diet on mature bone mineral content, structure, and mechanical properties.

Wohl GR, Loehrke L, Watkins BA, Zernicke RF.

McCaig Centre for Joint Injury and Arthritis Research, Department of Surgery, University of Calgary, 3330 Hospital Drive NW Calgary, AB, T2N 4N1, Alberta, Canada.

Diets with a high saturated fat content can produce deleterious effects on the absorption of dietary calcium and consequently an adverse effect on bone mineralization in growing animals. Hence dietary fat may have long-term consequences for skeletal health and skeletal pathologies such as osteoporosis. Whether a diet high in saturated fat has similar negative effects on adult bone, however, remains unresolved. Thus, we investigated effects of a high-fat diet on mature bone structure and mechanics. Adult (40-week-old) roosters were maintained for 20 weeks on either a diet high in saturated fat (HF) or a low-fat (LF) diet. Cortical bone samples (tarsometatarsus) were tested mechanically in three-point bending, and cancellous bone cores from the femoral condyles and tibial plateau (four sites per knee) were tested mechanically in compression. Cortical bone cross-sectional areal data were also compared among the groups, and bone mineral content (BMC) was determined (by ashing) for both cortical bone and cancellous bone samples. There were no significant high-fat diet effects on mature cortical bone mechanical properties, geometric structure, or mineral content. Diet, however, did affect cancellous bone composition. For example, LF cancellous BMC was significantly greater than HF. Mechanical properties of the cancellous bone showed similar trends such that LF cancellous bone strength was consistently greater than HF. The potential for adverse effects of a HF diet on intestinal calcium absorption in the mature animal may be more apparent in cancellous bone, with its faster rate of turnover, than in cortical bone. Changes in cancellous bone structure and mechanical properties, related to dietary saturated fats, may have implications for understanding the role of nutrition in skeletal health and prevention of pathological bone loss (osteoporosis).

[arena]

Also nicht ganz so positiv (laut der letzten, die 1. ist etwas zu kurz)

[rantanplan]

Inwieweit Ketodiäten die Knochengesundheit beeinträchtigen, ist nicht ohne weiteres zu beantworten. Theoretisch hat das ungünstige Säure-Basen-Verhältnis langfristig negative Auswirkungen, so dass es sicher angebracht ist, darauf zu achten, genügend Calcium und Vit. D aufzunehmen.