Two Randomized Trials Demonstrate Lactic Acid Supplementation in Pet Food Inhibits Dental Plaque, Calculus, and Tooth Stain in Cats

BACKGROUND: Dental concerns are some of the most common health problems affecting companion animals. A variety of foods, treats, and chews comprising different mechanical and chemical technologies have been investigated as a means of promoting oral health. Here, we investigate the chemical technology, lactic acid added to a commercially available food, for its ability to inhibit dental plaque, calculus, and tooth stain accumulation in cats. METHODS: Two separate feeding trials assessed the utility of a nutritionally complete feline maintenance food supplemented with lactic acid to reduce oral substrate accumulation (dental plaque, calculus, and tooth stain) in cats. After a calibration study identified high and low dental plaque formers, 45 cats were randomized to 1 of 2 test groups (food with 1.2% lactic acid supplementation) or control (food without lactic acid supplementation) groups, stratified based on their calibration scores. Data were collected on a monthly basis for 3 months. The second study randomly assigned 24 cats to either the test or control groups for 1 year, with data collected at the 6- and 12-month time points. RESULTS: In the 3-month study, reductions in dental plaque, calculus, and tooth stain accumulations were observed at the 2-month assessment in both test groups compared with control (P < .05 for test group 2). The 1-year study showed that these reductions in oral substrate accumulation persisted through the 6- and 12-month time points (P < .05). CONCLUSIONS: Taken together, these studies demonstrate that lactic acid supplemented at 1.2% in a feline maintenance food significantly inhibits oral substrate accumulation.