Question

I recently noticed that a national brand of feed, labeled as low-carb, has a total of 20% sugars and starches, which is definitely not low-carb in my book! How can this be?

Answer

The feed industry tends to categorize low-, moderate-, and high-starch feeds with NSC (nonstructural carbohydrates) ranges for each. Feeds containing less than 20% NSC are generally referred to as “low-starch,” whereas those with less than 12% NSC are considered very low starch. Concentrates with NSC levels in the 20s are referred to as moderate or controlled starch. Traditional performance formulas are considered high-NSC feeds and are usually greater than 30%.

Some horses with metabolic conditions may tolerate a slightly higher NSC than others. For example, a PSSM type 1 horse that is extremely sensitive to starch and sugar would do best on a feed like Re-Leve Original that has a very low NSC of 10%. On the other hand, some horses with Cushing’s, who are not insulin resistant or overweight, can safely consume a product with 20% NSC.

Some feeds, such as the one you saw, are appropriate for almost all metabolic conditions since they are considered concentrated ration balancer pellets, and only a small portion will be fed. The actual amount of starch and sugar consumed in a meal of 0.5-1 lb (0.2-0.5 kg) would be quite a bit lower than a meal of 2.5-5 lb (1.1-2.3 kg) of a typical concentrate feed. For example, if a feed is 20% NSC and a meal is 0.5 lb (0.2 kg), then the meal will only provide 1.6 oz of starch and sugar. In contrast, 3 lb (1.4 kg) of a 20% NSC feed provides 9.6 oz of starch and sugar. Less than 2 oz of NSC in a meal will cause very little glycemic response, if any at all.