No matter what the age, breed, occupation, or health status, horses do best when fed a diet that is as close as possible to what nature has provided for them. “As close as possible” will mean different things for different horses, but the fundamentals are the same for all. The basis of the horse’s natural diet is a wide variety of plants that changes with the season:

* mostly grasses
* some legumes (clover, alfalfa, other little trefoils)
* various other meadow and woodland plants

Horses grazing in a natural setting have been observed to select from over 40 different species of plants. The variety comes not just from the great range of plant species available, but also from the variations in plant types, parts (roots, stems, leaves, flowers, fruit, seeds), and nutrients (phytonutrients) with the different seasons.

In contrast, the typical domestic horse’s diet is very limited in variety, particularly if the horse has little or no access to natural pastures, woodlands, or other uncultivated areas.
Most horses are fed a single type of hay (e.g. orchard grass or timothy), day in, day out. While there may be a few other plants mixed in, the hay is predominantly a monoculture
—a single species.

Not only is variety of phytonutrients lacking, so too is their quality and quantity, as processing and storage cause a decline in vital nutrients, particularly some vitamins 
and various other antioxidants.

Furthermore, even if the horse has access to pasture, many pastures are overgrazed, seeded with just a few human-selected plant species, or treated with herbicides, so 
they provide little variety of plant nutrients.

Why is variety so important?

Horses are designed to get all of their nutrient needs from plants and the soils in which they grow. But the twin keys here are quality and variety. The more variety of fresh, minimally processed foods from well-tended soils you feed, the less you’ll need to rely 
on supplements to meet your horse’s needs, and the healthier s/he will be.

That’s because providing a variety of high quality foods makes it more likely that the horse will get all that her body needs in the way of primary nutrients and beneficial cofactors, such as vitamins, minerals, and antioxidant compounds, just from her food. All of these nutrients are essential for health, tissue repair, vitality, and longevity.

(Variety also has a protective influence in the diets of horses needing more calories than can be provided by the natural forage-based diet. For example, feeding a mix of whole grains, some oily seeds [e.g sunflower seeds], and perhaps a little beet pulp if needed, lessens the risks of feeding a high-carb diet in performance horses, youngsters, and broodmares.)

Obviously, horses can survive on the limited variety provided by the typical diet, but they do not thrive on this diet. Over time, various chronic health problems develop that we take for granted are simply caused by aging.

The truth is that these conditions are largely preventable with good management, which includes good nutrition. The same can be said for other common ailments, such as colic, heaves, laminitis, and exercise-related muscle disorders.

Most processed horse feeds are fortified with vitamins and minerals, and some products these days even contain extra antioxidant substances. However, in the vast majority of cases these processed foods and supplements use synthetic vitamins and inorganic or, at best, chelated minerals, for which bioavailability (absorption and utilization by the body) 
is poor to moderate. In contrast, the vitamins and minerals in plants generally are much more bioavailable.

While vitamins and minerals, and even antioxidants, can be added to the ration, the remarkable variety, complexity, and synergy of the substances contained in whole foods cannot be matched in a laboratory or factory.

For example, natural vitamin E is far more complex than just a mix of isolated tocopherols. And natural vitamin C is way more than just ascorbic acid. There are several cofactors associated with each of these apparently simple vitamins in their natural forms. These cofactors play essential roles in how the vitamin is taken in and functions in the body. Same, too, with minerals incorporated into plant molecules or suspended in plant cells 
in ionic or colloidal form.

Nature has already figured all of this out for the horse, and we would be wise to follow 
her lead. Time and time again in my practice I have seen chronic medical, performance, 
and even behavioral problems spontaneously resolve just by putting the horse onto a 
more natural diet. It’s as Hippocrates is reported to have said: “Let thy food be thy medicine, and thy medicine thy food.”

(These concepts are explored further in the first chapter of the anima Herbal Recipe Book.)