10 Best Weight Gain Supplements For Horses 2026 in the United States

The Horse XL supplement by Equinety is designed primarily to support injury repair, joint health, and hoof strength in horses of all ages and breeds. Its key benefit is its high-quality blend of essential amino acids, which are important building blocks for muscle and tissue repair. The supplement is free from fillers, soy, sugar, and artificial additives, making it a clean, natural option that is safe for regular use. One tub provides a 100-day supply with a simple dosing routine.

This product focuses on providing protein through amino acids rather than delivering calories or fats to increase a horse’s weight. It comes in an unflavored powder form that is easy to mix with feed, supporting palatability. While it does not contain added vitamins or minerals targeted at weight gain, its natural and pure ingredients contribute to good digestibility, which supports overall health and nutrient absorption.

Horse XL also claims to aid mental focus and immune health, extending its benefits beyond joint and hoof care. It is a solid choice for enhancing recovery, muscle repair, and joint function with a clean, vet-approved amino acid formulation. For those seeking a supplement specifically aimed at weight gain with higher calories, fats, and comprehensive vitamins and minerals, other products may be more suitable.

The Purina Amplify Equine High-Fat Horse Supplement is designed for a variety of horses, including those in maintenance, breeding, and performance. One of its standout strengths is its high caloric content which is beneficial for horses that need to gain weight. The presence of added antioxidants, including Vitamin E, helps address the harmful effects of free radicals, potentially improving health.

It also features an optimal fatty acid profile to support the immune system and promote a healthy skin and coat, which is a significant advantage. Additionally, its calorically dense formula with controlled starch means you can feed your horse less while still providing adequate nutrition, making it cost-effective in the long run.

The supplement is a powder form and comes in a 50 lb bag, with a rice flavor which should be palatable for most horses. It is suitable for all life stages, making it versatile for a wide range of horses. However, at 54 pounds, the product is quite heavy and might be cumbersome to handle. Therefore, it is recommended to consult with a veterinarian to ensure it meets your horse's specific dietary needs.

Formula 707 Weight Gain Equine Supplement is designed to help horses, especially those that are hard to keep or older, gain and maintain healthy weight with improved muscle tone and energy. It delivers calorie-rich nutrition primarily through vegetable fat, which is easily digestible and boosts energy. The supplement also provides high-quality protein with essential amino acids needed for muscle building.

Its powder form comes in convenient daily fresh packs that protect the product from moisture and sunlight, making it easy to use on the go or during events. This packaging ensures the supplement stays fresh and maintains its palatability, which horses generally seem to accept well. The pre-measured packs simplify feeding and reduce waste, but the powder form means you’ll need to mix it into the horse’s feed properly to ensure full intake.

With a strong customer rating around 4.6 stars, many users find it effective and convenient. This supplement is well suited for horse owners looking for a reliable and easy way to support weight gain, especially for senior horses or those with metabolism challenges.