7 Reasons to Feed More Hay in Winter Months

1. Long-Stem Hay Generates Internal Heat

One of the biggest advantages of long-stem hay, also known simply as baled hay, is its ability to produce internal warmth through digestion. When a horse chews and digests forage, the gut muscles must contract more vigorously to move that fibrous material through the digestive tract. This process requires energy, and the body releases heat as a by-product.

This phenomenon is known as the “heat of digestion” or “heat increment.” Essentially, the more your horse eats forage, the more heat their body naturally produces from the inside out. Grain, oils, and highly processed feeds may contain more calories per pound, but they do not generate the same level of internal heat because they’re much easier for the body to break down.

This makes long-stem forage one of the most valuable tools you have when temperatures plummet. If you’re wondering how to help your horse stay warm safely and naturally, the best answer is to feed more hay in winter.

2. Increased Fiber Intake Supports Steady Body Temperature

Hay is rich in structural fiber—the kind that keeps the digestive system moving and fuels the microbial population within the hindgut. When you increase hay during winter, you’re supplying a longer-lasting, slow-burning energy source. This helps your horse maintain a more stable body temperature throughout the day and especially overnight, when temperatures usually hit their lowest point.

Horses are designed to forage continuously. In winter, when pasture quality declines or disappears completely, hay becomes the primary source of essential fiber. Feeding more hay helps mimic their natural grazing behavior and supports the energy requirements needed to stay warm around the clock.

3. Long-Stem Hay Encourages Increased Water Consumption

Another overlooked benefit of long-stem hay is its natural tendency to increase thirst. Because hay contains more dry matter than pellets, cubes, or grain, horses often drink more water when eating higher amounts of traditional baled hay. This is especially important in colder months when horses commonly consume less water due to chilly temperatures.

Dehydration is one of the leading contributors to impaction colic, and winter is the season when many horses are at highest risk. Simply increasing hay can support hydration and reduce the likelihood of digestive slowdowns. When in doubt, it is always safer to feed more hay in winter to promote healthy drinking habits.

4. Concentrates Don’t Create the Same Heat as Forage

While concentrates like grains and oils provide high calorie density, they do not require the same amount of muscular effort from the digestive tract. Because they break down quickly, the gut produces far less natural body heat.

This distinction is critical. Horse owners sometimes assume that increasing grain will help a horse maintain weight or warmth in winter, but the digestive process behind grain simply does not generate the same warming effect as hay.

For overall digestive health, stable energy, and natural internal warmth, forage should be the foundation of your winter feeding program. Grain can supplement calories if needed, but forage is what keeps your horse warm from the inside out.

5. Forage Fiber Supports a Healthy Gut Microbiome

A healthy hindgut depends on the right balance of fiber. The microbial community living in the gut—responsible for fermenting forage and generating vital nutrients—relies on consistent long-stem roughage. Increasing hay during winter provides the continuous fiber supply needed to keep these microbes functioning properly.

A strong microbiome helps:

• Improve digestion

• Stabilize energy levels

• Support immune health

• Reduce the risk of colic

• Maintain proper gut motility

When you feed more hay in winter, you’re not only supporting warmth but also building a healthier digestive environment that benefits your horse year-round.

6. Soluble Fiber Feeds Support Warmth & Hydration

Feeds that contain high levels of soluble fiber—such as beet pulp and soybean hulls—also require more digestive effort than standard grain. This makes them excellent additions to a winter diet.

Products like Integrity Lite and Integrity Adult/Senior, which list beet pulp and soybean hulls as their first two ingredients, provide a significant source of soluble fiber. These ingredients promote strong gut contractions and encourage increased water intake, helping support both digestion and hydration during the cold season.

While they do not replace the need for long-stem hay, they can be valuable supplements when extra calories or easily digestible fiber are needed.

7. Water Temperature Affects Hydration —  Especially in Winter

Even the best hay program won’t help much if your horse isn’t drinking enough water. Horses naturally drink less when water is cold. Water in underground piping may average around 55°F during much of the year, but in winter it can drop to 45°F or lower.

Cold water is far less appealing, and many horses will reduce their intake significantly. Ideally, drinking water should be maintained at 55°F or warmer to encourage healthy consumption, especially when increasing hay. When you feed more hay in winter, your horse needs to drink more water; warm water helps make that happen.

Using heated buckets or automatic waterers with built-in heaters can make a substantial difference in keeping your horse hydrated and reducing the risk of impaction colic.

The Bottom Line: Feed More Hay in Winter for Health, Warmth, and Digestive Support

As winter settles in, your horse’s metabolism shifts to maintain body warmth, support digestion, and stay hydrated. Long-stem hay provides the fiber, energy, and internal heat the body needs to function optimally during cold weather. Grain, pellets, and oils simply cannot replicate the natural warming effect of forage.

By choosing to feed more hay in winter, you help your horse:

• Generate natural body heat

• Maintain a stable core temperature

• Drink more water

• Support gut health and microbial balance

• Reduce the risk of colic

• Receive consistent fiber and energy

Increasing hay during winter months is one of the simplest, most effective changes you can make. It keeps horses healthier, warmer, and more comfortable throughout the season—starting from the inside out.