If you’re like most compassionate and attentive gerbil owners, you’ll want to know which food will give your gerbil absolutely everything they need to thrive.
We wrote this article after spending many hours delving into the latest available resources, as well as surveying the online gerbil owner community.
Unfortunately, there isn’t actually a ton of research into what pet gerbils need in terms of nutrition, and there’s also a lot of conflicting information out there on the internet.
After all, gerbils haven’t been kept as pets for even 100 years yet. So we have much less information about what they need than we have for cats or dogs.
Gerbil Nutritional Requirements
Gerbils have a particular macronutrient profile that they need to survive and thrive. What are macronutrients?
Macronutrients are the three primary categories of nutrients you (or your gerbil) consume. Macronutrients provide most of the energy we get from foods. The three macronutrients are carbohydrates, protein, and fat.
According to the detailed studies mentioned above and other sources, gerbils have the following nutritional needs in terms of macronutrients.
Gerbil protein requirements
Protein is one of the most important parts of a gerbil’s diet to pay attention to. That’s because gerbils need a relatively high amount of protein in their diets, and many commercial gerbil foods do not contain enough protein (or may even contain too much).
Many gerbil foods were originally formulated for hamsters, which have slightly different dietary needs.
It’s also important to note that young gerbils and nursing mother gerbils need more protein than a fully grown, non-breeding gerbil:
- A young gerbil’s diet should contain 16% to 20% protein.
- An adult (fully grown) gerbil’s diet should contain 12%-16% protein.
It’s generally recommended to avoid foods that contain more than 20% protein, although adverse effects at higher levels haven’t been officially reported as far as we could find.
A higher level of protein mostly means that your gerbils will be consuming and absorbing lower levels of other vital nutrients, which could be detrimental.
Gerbil fat requirements
No absolute minimum or maximum fat intake has been established for gerbils to date.
It is known that gerbils can survive on diets containing as little as 2% dietary fat or as much as 20%.
A general consensus is that gerbil diets should contain 5%-7% fat. Anything over 9% fat should generally be avoided.
Gerbil carbohydrate requirements
The rest of a gerbil’s diet and the majority of what they consume is made up of carbohydrates. This will usually turn out to be between 75% and 85%.
Carbohydrates include starches, sugars, and fibers which are found in the grains, seeds, vegetables, and fruits that make up much of a gerbil’s diet.
Gerbil fiber requirements
Although fiber is part of the larger carbohydrates category, fiber should not make up too much of a gerbil’s diet. This often surprises new gerbil owners because many small animals, like rabbits and guinea pigs, live on mostly fibrous foods like grass and hay.
It’s generally agreed that a gerbil’s diet should have a maximum of 12%-15% fiber.
Special Dietary Considerations for Gerbils
There are some common misconceptions about gerbil diets that are easily cleared up by reviewing the research. Here are some of the most important considerations for feeding your gerbils.
Gerbils are omnivores
Many people assume that all small prey animals are herbivores, only consuming vegetables, grasses, seeds, nuts, and fruits.
But gerbils are naturally acclimated to eating both plant-based foods and animal proteins. This is why their protein needs might be higher than many people expect.
In captivity, gerbils can get this needed protein through plant sources like seeds, as well as by eating dried mealworms.
(We like these dried mealworms by Kaytee.)
Gerbils don’t need a high-fiber diet
Unlike guinea pigs and some other small animals, gerbils (as well as hamsters) do not thrive on a high-fiber diet.
Their stomach is not designed to digest a large amount of fiber like that of a guinea pig or rabbit. That means that foods made mostly of hay or grass are not suitable for gerbils or hamsters and can be very detrimental to their health.
This is important to understand because it means gerbils should not be given pelleted foods that are intended for guinea pigs, rabbits, or other animals that require a high-fiber diet.
Gerbils need daily access to water
Although gerbils are arid-acclimated animals, they still need access to water in the form of fresh drinking water and moisture-rich snacks like fresh fruits and vegetables.
Gerbils consume (in the form of fresh water or hydrating foods) 4 to 10 mL of water per day.
We recommend using a water bottle rather than a water bowl. Gerbils will bury their water bowl in bedding the very first chance they get!
Gerbils don’t care about the color of their food
A question that many gerbil owners have is: why do companies put artificial colors and dyes in gerbil food?
The answer is that bright colors draw the eye when you’re shopping for a food mix in the pet store. However, gerbil owners no longer look for bright and colorful foods and instead pay close attention to the ingredients and nutritional value of their pets’ food.
Luckily, this practice is becoming less and less common as companies and gerbil owners are finally getting on the same page about gerbil health needs.
Still, it’s important to check any food you give your gerbils to ensure that it doesn’t contain food coloring or dyes. There isn’t sufficient research to tell us what, if any, negative impacts these dyes can have on our pets.
But what we do know is that they do not provide any benefits and only come with unnecessary risk.
What to Feed Your Gerbils
A gerbil’s diet in captivity should typically have three components: lab blocks (also known as pellets or pelleted food), seed mix, and fresh fruits and vegetables.
It can also include an animal protein source like mealworms, which are sometimes included in gerbil seed mixes.
Lab blocks for gerbils
Look for lab blocks or pellets that have high protein, which can balance out the lower protein content of many seed mixes, as well as the low protein of fresh fruits and veggies.
Pelleted food also ensures that your gerbil doesn’t suffer the negative effects of selective eating, where they pick out the tasty pieces and don’t get the full nutritional value of the food.
Note: Gerbils should not be given a diet of exclusively pellets or lab blocks. They also need a seed mix and fresh fruits and veggies.
Here are our favorites:
- ENVIGO-Harlan Teklad 2014 Global Rat Food Pellets
- Mazuri Rat & Mouse Diet
- Kaytee Forti-Diet
- Oxbow Adult Rat (not Oxbow Gerbil & Hamster)
Seed mixes for gerbils
Seed mixes are essential for gerbils since they provide an opportunity for foraging. We recommend scatter-feeding your seed mix for your gerbils so that they have to engage their natural foraging instincts.
Too much of a seed mix, however, without lab blocks as a supplement can lead to picky eating.
Here are our seed mix recommendations for gerbils:
- Robin’s Gourmet Pellet-Free Gerbil Food Mix
- Sunburst Gourmet Food Mix for Hamsters & Gerbils
- Vitakraft Vita Smart Rat and Mouse Food
- Higgins Vita Garden Hamster & Gerbil Food
Fresh fruits and vegetables for gerbils
You can and should give your gerbils some fresh fruits and vegetables every other day.
Make sure to give them a small portion (about two to three raisin-sized bites per gerbil) and remove uneaten fresh fruits and veggies after an hour. This prevents your gerbils from eating moldy or spoiled fruits and vegetables.
Some great vegetables and fruits to give your gerbils include:
Treats for gerbils
In addition to lab blocks, seed mix, and fruits and vegetables, you can give your gerbil the occasional treat such as mealworms, dried fruit, or fatty seeds like pumpkin seeds and sunflower seeds.
Limit sweet and fatty foods like large seeds to every other day or every three days, and only provide a small portion at a time.
We advise against commercial treats like yogurt drops, as these contain high amounts of sugar and can lead to diabetes. If you do provide sugary snacks, limit them to a raisin-sized portion once per week.
How Much to Feed Your Gerbils
Gerbils vary in how much they eat and how quickly they eat. However, a good rule of thumb is to feed each gerbil 1 tablespoon of food per day.
You can provide a tablespoon of all of their foods together (seed mix, lab block, and fresh foods), or provide different foods on a feeding schedule.
An example of this would be giving a tablespoon (per gerbil) of lab block food on Monday, Wednesday, and Friday, and a tablespoon of fresh fruits and veggies plus seed mix every Tuesday and Thursday.
Here’s a breakdown of how much of each type of food you should be feeding your gerbil:
15% – Fresh fruits and vegetables
35% – Seed mix
50% – Lab block
What Do Gerbils Eat in the Wild?
Mongolian gerbils originate from the Amur River basin in eastern Mongolia. They’ve only been kept as pets since about 1935, so they’re still naturally acclimated to their native habitat.
Gerbils haven’t been domesticated long enough to adapt to the conditions we keep them in as pets, as cats or dogs have. That means we have to do our best to simulate their natural environment as much as possible.
That means providing them with plenty of space, enrichment, and a diet that closely resembles what they’d find in the wild. So what do gerbils eat in their natural habitat?
Wild gerbils eat a mixture of grass (both the roots and the grass itself), various roots and bulbs, seeds, leaves, and some insects.
Do gerbils eat grass?
Gerbils in Mongolia feed partly on the wild grasses that grow in that region. It’s important to note that gerbils don’t require a high-fiber diet.
In fact, gerbil stomachs aren’t equipped to process a large amount of fiber and can’t absorb much nutrition from fibrous foods. This means that wild gerbils probably rely mostly on the roots and bulbs of wild grasses.
This aligns with their burrowing habits, as they would have to dig tunnel systems and burrow underground to access this food source.
The primary grasses that Mongolian gerbils eat in the wild include:
- Mugwort (Artemisia sieversiana and Artemisia commutata)
- Saltwort (Salsola collina)
- Bristle grass (Setaria viridis)
- Lyme grass (Leymus chinensis)
Do not give your gerbils grass from your yard! This type of grass isn’t what they’re adapted to, and it can contain harmful pesticides and fertilizers.
Do gerbils eat bugs?
Many people are surprised to learn that gerbils aren’t herbivores; they’re omnivores who feed on plant foods as well as invertebrates (insects).
In their natural environment, gerbils likely encounter and feed on different types of flies, various worms, crickets, beetles, grasshoppers, insect larvae, and more. These insects provide ample protein, as well as hydration.
Many gerbil owners meet their gerbils’ need for insect protein by feeding them dried mealworms. However, seeds and nuts are also a valuable source of protein, and mealworms aren’t always necessary.
Do gerbils eat seeds?
Another large part of most wild gerbils’ diets is seeds. It’s thought that gerbils probably feed on insects as their primary protein source when they’re available.
Gerbils seem to seek out seeds and hoard them for seasons when insects aren’t as readily available. This means that seeds are more of a secondary source of nutrition for many gerbils.
However, seeds are an essential part of a captive gerbil’s diet, as they provide a wide range of essential nutrients.
Do gerbils eat vegetables?
Leafy plants and plant roots are a vital part of a wild gerbil’s diet. Because they live in arid conditions, wild gerbils get most of their water from the foods they eat. This includes insects, as well as vegetables and fruits.
In their natural environment, Mongolian gerbils feed on native herbs and other leafy foliage, as well as some berries and fruits.
In captivity, some gerbils enjoy various fresh vegetables and fruits as a treat. However, they often prefer foods that can be stashed away, such as dried vegetables and fruit pieces.
Gerbil Dietary Needs FAQ
How much protein do gerbils need?
Gerbils need about 12%-16% protein in their diets.
How much fat do gerbils need?
Gerbils should have between 2% and 7% fat in their diets.
How much fiber do gerbils need?
Gerbils should have 10%-15% fiber in their diets.
How much should you feed your gerbils?
Feed each gerbil about one tablespoon of food per day, comprised of a mix of seed mix, lab blocks, and fresh fruits and veggies.
Do gerbils eat hay?
Gerbils can have hay, but they do not need it. The main benefit of hay for gerbils is that it’s a great additional nesting material and helps keep their teeth trimmed.
Do gerbils eat vegetables?
Yes, gerbils eat fresh vegetables as well as dried or freeze-dried vegetables. Fresh vegetables are a small but very important part of a pet gerbil’s diet.
Do gerbils eat fruit?
Gerbils enjoy a small portion of fresh or dried fruit every day or every other day. You should pay attention to how much fruit you’re giving your gerbils and limit it to one or two raisin-sized bites per day. This is to help prevent your gerbils from consuming too much sugar, which can lead to diabetes.
Do gerbils eat meat?
Gerbils are omnivores, which means they consume both plant proteins and animal proteins.
In captivity, gerbils do not need to eat meat because they can get their protein requirements from nuts, seeds, legumes, and other vegetable sources. However, many gerbils enjoy mealworms as part of their diet.
Can gerbils eat birdseed?
No, gerbils cannot be fed birdseed. Birdseed has a high percentage of fatty seeds, which isn’t good for gerbils.
Can gerbils eat cheese?
While gerbils can have a small amount of cheese as a treat very occasionally, it isn’t ideal. Gerbils are actually thought to be lactose intolerant, so any dairy can cause stomach distress.
Feeding Your Gerbils: Don’t Fret About a Percent
Understanding what a gerbil needs and wants in their diet isn’t easy. After all, we’ve only been keeping them as pets since the 1930s, which means we haven’t had much time at all to study them.
Additionally, gerbils haven’t been bred in captivity long enough for them to develop adaptive traits for living in captivity, which means that they still need basically the same diet as they would get in the wild.
While we’ve provided percentages for what a gerbil’s diet should contain in this article, it’s important to know that a 1%, 2%, or even 5% difference isn’t going to make or break your gerbil’s health.
If you’re feeding your gerbils close to the correct portions of fat, protein, and carbohydrates, you’re on the right track.
- “National Research Council (US) Subcommittee on Laboratory Animal Nutrition. Nutrient Requirements of Laboratory Animals: Fourth Revised Edition, 1995”. Washington (DC): National Academies Press (US). 1995. 6: Nutrient Requirements of the Gerbil. https://www.ncbi.nlm.nih.gov/books/NBK231920/
- Amur Heilong. World Wildlife Foundation. https://www.wwf.org.uk/where-we-work/amur-heilong
- DiBattista, D. “Voluntary lactose ingestion in gerbils, rats, mice, and golden hamsters”. Physiol Behav. 1992 Jul; 52(1):59-63. doi: 10.1016/0031-9384(92)90433-3. PMID: 1529014. https://pubmed.ncbi.nlm.nih.gov/1529014/
- Chen, Jack. “Meriones unguiculatus, Mongolian jird”. Animal Diversity Web. https://animaldiversity.org/accounts/Meriones_unguiculatus/#:~:text=Mongolian%20gerbils%20feed%20mainly%20on,water%20and%20fat%20extremely%20well.
- “Do Gerbils Need Hay? (If So, How Much And What Kind?)”. Pocket Pet Central. https://pocketpetcentral.com/do-gerbils-need-hay/