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 Farnam Weight Builder Horse Weight Supplement is designed to help horses maintain or gain optimal body condition by providing a high-fat, nutritionally balanced formula without added sugar, which reduces the risk of digestive issues. Its standout feature is the 50% fat content, supplying more calories than typical grains, making it effective for adding energy and weight safely. It also includes omega-3 fatty acids from flaxseed meal and stabilized rice bran, supporting healthy skin and a shiny coat, which is a nice bonus beyond just weight gain.

The powder form mixes easily with regular feed and is palatable, increasing the chance your horse will eat it willingly. The supplement is intended for all life stages and larger breeds, with flexible dosing up to two scoops daily depending on the horse's activity and weight goals. The 90-day supply and positive customer ratings indicate good value and satisfaction among users.

This supplement suits horse owners needing an easy, fat-focused calorie boost for weight gain or maintenance without sugar, especially for horses sensitive to grain sugars or prone to digestive upset.

The Super Weight Gain 10 lb supplement by Horse Guard is designed to help horses gain weight in a healthy manner. It uses quality protein sources rather than relying on sugars and starches, which is a positive for maintaining health. The inclusion of powerful live probiotics, prebiotics, and yeast aids in digestion and helps horses get the most out of their feed, addressing key concerns about digestibility.

The supplement also ensures that horses receive essential vitamins and trace minerals, such as Vitamin E and Selenium, supporting a healthy immune system. The use of full oil soybeans provides cool energy without making horses hyperactive, which can be beneficial for maintaining a balanced temperament while gaining weight. The product uses pharmaceutical-grade ingredients, which promises high bio-availability and quality assurance.

It is important to note that the flavor is listed as 'Other,' which might affect palatability for some horses. The supplement comes in powder form, and the feeding directions specify a daily regimen based on the horse's current body weight, which might require careful adherence. Weighing 10 pounds and packaged within standard dimensions, this supplement is particularly suitable for adult horses needing support with weight gain, stomach health, and coat condition.