Shelf Life of Vitamins and Supplements for Horses
Updated August 16, 2024 | By: Dr. Lydia Gray
"Being in the south, I am concerned about keeping our tub and bag supplements out in the humidity and heat. How much will temperature and humidity affect my supplements and grain “shelf life” and effectiveness? What are the signs to look for in spoilage, if that is possible?"
- LG, Virginia
Dear LG,
That’s a great question! Unfortunately no threshold has been established as to the specific levels of heat and humidity that will adversely affect supplements. There’s just too much variation in individual formulas and ingredients to be able to give you one answer that will work for all products. However, I can offer you some general guidelines.
Consider SmartPaks or Smaller Buckets During Warmer Months
Since you live in the south, if you buy your supplements in buckets, I suggest only buying the smaller buckets that last about one month at a time, at least during the summer months. Buying small amounts (and therefore only keeping the supplements sitting in the barn for a short period of time) will definitely help prevent them from being damaged by heat, moisture (humidity) and oxygen.
Reseal the buckets carefully after each use – that includes resealing the inner plastic bag if your bucket has one. Better yet, consider SmartPaks! This will ensure that each daily dose is sealed against oxygen and moisture (vs. the whole bucket of product being exposed each time you open it), and that you’ll receive a fresh batch of product every four weeks.
Storage and Sunlight Exposure
Keep your SmartPaks and buckets out of the sun too, as light can also cause products to break down. Independent studies have shown that storing SmartPaks in the plastic drawer we provide with the blue plastic insert in the front blocks almost 100% of damaging UV rays.
Regarding the signs of spoilage, this too is difficult to answer because of the wide variety of formulas and ingredients out there. A change in color, consistency or smell doesn’t necessarily mean a supplement has “gone bad.”
However if you’re concerned about a particular supplement, contact the manufacturer, describe what you’ve noticed, and they should be able to tell you if that’s normal for the product or a potential problem.
Additional Resource: Mineral interactions, storage, and nutrient potency of mixing supplements for horses.