What the Heck Is low starch balancer?

http://news.fourthpillarnews.com/story/507205/with-half-of-britains-horses-overweight-bifid-launches-grainfree-lowsugar-feed-for-the-nations-gooddoers.html

Gentle horse feed for sensitive stomachs, designed to support digestive comfort, intestinal health and easy nutrient absorption. A low sugar high-fibre formula with naturally sourced ingredients to help maintain steady digestion and overall health.