Effect of Dietary Starch Sources on Canine Lipidemia

In the literature

Teixeira FA, Machado DP, Jeremias JT, Queiroz MR, Pontieri CFF, Brunetto MA. Starch sources influence lipidaemia of diabetic dogs. BMC Vet Res. 2020;16(1):2.

The Research …

Hyperlipidemia is a disturbance of lipid metabolism that results in increased serum lipids (ie, triglycerides, cholesterol, or both). Hyperlipidemia in a fasted state is abnormal and indicates accelerated synthesis or reduced degradation of lipoproteins. Hyperlipidemia due to a lipid disorder is primary (ie, a defect of lipoprotein metabolism) or secondary (ie, characterized by increased lipoproteins, decreased lipoprotein catabolism, or both). 

This randomized, crossover, double-blinded study evaluated the effects of 3 high-starch diets (ie, dietary peas/barley, peas/barley/rice, corn) in 12 dogs with stable diabetes and a history of hyperlipidemia. Dogs were fed a basal diet (9% fat on a dry-matter basis) for 60 days, then randomized to be fed each of the test diets for 60 days. The test diets had similar percentages of crude protein, fat, fiber, and ash but differed in sources of starch (ie, peas and barley vs corn). At the end of the test period, plasma triglyceride and cholesterol curves were measured over 10 hours.

Mean plasma triglyceride levels were significantly lower after the pea and barley diet trial as compared with the basal diet trial at fasting and 8 hours postprandial and as compared with the corn diet trial 4 hours postprandial. Mean, minimum, and maximum plasma cholesterol levels were significantly lower after the pea and barley diet as compared with the corn diet at all time points except during fasting; there were no differences as compared with the basal diet. 

Feeding a lower-fat diet is considered critical for hyperlipidemia management. The results of this study suggest that dietary ingredients may also play an important role. Although dogs fed the pea and barley diet had lower cholesterol at several time points as compared with dogs fed the corn diet, hypercholesterolemia in dogs is believed to be less clinically important than hypertriglyceridemia. In addition, a complete dietary analysis of the diets was not specified, making it challenging to interpret the results. Barley contains β-glucans (ie, polysaccharides found in the bran of cereal grains that have several reported health benefits in humans^1,2) and has been evaluated in humans for its cholesterol and lipid-lowering effects.³ Pea protein has been found to reduce triglyceride and cholesterol levels in some species.^4-8 Although the mechanism is not fully understood, the benefit of pea protein may be due to increased hepatic activity of low-density lipoproteins, resulting in increased clearance of low-density lipoprotein cholesterol, decreased synthesis of fatty acids, and increased excretion of bile acids in feces.^4-7

… The Takeaways

Key pearls to put into practice:

• Hyperlipidemia in a fasted dog or cat is abnormal and should be managed.

• Dietary and drug interventions can decrease the morbidity associated with hyperlipidemia.

• Dietary ingredients, fiber, and several nutrients (eg, β-glucans), in addition to reduced dietary fat, may play an important role in management of patients with hyperlipidemia.