Rat Nutrition
by Sarah Paterson-Farrand ©

Understanding the Fundamentals
Offering a nutritionally complete diet is one of the most fundamental responsibilities of owning any type of pet. Good nutrition is the primary key to living a long, healthy life, so diet is not to be taken lightly. With the potential to have lasting effects on your rat’s health, serving a nutritionally complete diet should be, in fact, taken very seriously.
The basics of a good diet begin with understanding your rat’s nutritional needs. Actually, their requirements are quite similar to that of our own, with a few exceptions like calcium, manganese, vitamin K, and vitamin B12, all of which they need considerably more than we do. But, the easiest way to determine what your rats need in a healthy diet, is to look at a natural model, that is, how they eat in the wild. Combine that knowledge with the nutritional requirements that have been established by organizations such as the National Research Council, and you will have an ideal diet for your rats.
So, what do rats eat in nature? Rats are classified as opportunistic omnivores, which basically means that they will eat just about anything including seeds, nuts, grains, vegetables, fruits, meats, and invertebrates. Over all, rats prefer starch and protein rich foods, but they are also partially predatory. Some of their nutrients are best obtained from an animal source, so bugs, lizards, and even carrion, may be on the menu. Also, on a side note, because rats are omnivores, they get all the sodium they need from their diet, so it is not necessary to provide a salt lick.
While looking at the natural model, feeding behaviors should also be noted. In the wild, rats typically have to scavenge for food and will stockpile what they find. Our domestic rats can often be seen hoarding food as well. But, we should also indulge their natural seeking instincts by offering bits of food here and there in their cages, along with their usual bowl of food. This provides exercise and stimulation and will help keep them happy and healthy.
Another important feeding behavior to understand is sampling. In the wild, new sources of food are approached cautiously and are initially only sampled. This instinct allows a rat to determine if a particular food is safe before eating more. If a food was bad and eaten in larger amounts, the rat would still have to digest it because a flap in the stomach, which covers the esophagus, prevents them from vomiting.  Often, safe foods are learned from parents or other social adults. Interestingly enough, once a rat has sampled an item and deemed it safe, it will freely feed on that item from that point forward, as will its offspring. So, don’t feel bad if new foods are approached without enthusiasm to begin with. However, sometimes in domestic rats, like our pets, you will no longer see this cautious behavior. It doesn’t mean that your rats do not have this instinct; it simply means that they trust you. As they would freely eat new things that their parents or social partners ate, they too would not be concerned with something you gave them. Consider it a complement!
The last feeding behavior that should be mentioned is coprophagy. Coprophagy is quite plainly, the eating of feces. From the feces, the rat can get folic acid, vitamin K, and biotin, which may not have been fully absorbable prior to digestion.
Now that you know what rats are designed to eat, the next step is to apply this to what is known of their nutrient requirements. This is more than just learning what your rats need to survive, but what they need to thrive. Starting with the basics, adult rats need about 10 - 15% protein, 5% fat, and roughly 75% carbohydrates. Protein requirements are higher in the case of growing, pregnant, or lactating rats, requiring a protein level around 20%. Proteins and fats are necessary for the building and repairing of all the body’s tissues and for energy. However, carbohydrates provide the main source of energy for rats.
Deficiencies in these major building blocks of nutrition can lead to weight loss, weakened immune systems, poor skin and coat, infertility, listless behavior, starvation, and even death. But, feeding too much of something can also be bad. Rats are prone to a reaction to excess protein, and may develop scabs and hair loss if given too much. In fact, according to Debbie Ducommun, if a rat eats a meal very high in protein, such as those with loads of fish meal, a rat can actually become hyper and anxious.
In the case of fat, it is the type of fat you feed that is important, just as it is with people. Excess saturated fats can lead to the increased risk of obesity, heart disease, stroke, arthritis, and tumors. And, lately, there has been significant research on the health impacts of the worst fats, the trans-fatty acids, which are unfortunately found in most processed or packaged foods. So, although these fundamental elements should always be accessible, they need to be in the right proportions to have a healthy diet.
Fiber is also important to a healthy digestive system, and one should feed whole grains rather than the bleached forms. Beyond the basics, there are all the vitamins and minerals essential to proper nutrition.

Vitamins and Minerals
The chart below indicates the average amounts of vitamins that a rat needs in its diet, as well as what a deficiency may cause. Where the amount is in mg/kg, it is kg of diet. Of course, to truly make sense of the diet, you should understand why and how these nutrients work. This is also a good time to point out that the best way to get vitamins, or any nutrient, is to do so naturally with fresh, whole foods rather than processed diets you get in a pet store. So, there are also some general ideas of some foods that supply these essential nutrients within the chart, as well as following in the more in depth descriptions. This is by no means, an exhaustive list, and is only meant to provide a basic understanding of these essential elements of the diet.

Vitamin A – This fat-soluble vitamin comes in two natural forms, retinol from animal products, and beta-carotene from plants. Vitamin A is essential for healthy eyesight, bone formation, immune response, and the growth and repair of tissues. Retinol is found in fatty fish, eggs, butter, and some cheeses. Beta-carotene is found in parsley, spinach, sweet potatoes, tomatoes, and apricots. However, retinol can also be toxic if given in extreme excess, where the beta-carotene form of Vitamin A is safe at any dose. In fact, there are leading studies to suggest that high intake of retinol adversely effects bone health. This is something to keep in mind for us, as well!

– This nutrient is often classified as part of the ‘B’ vitamins as well, and is found in meats, yeast, nuts, and citrus. It functions with the other vitamins for proper fat metabolism and for cell structure.
Vitamin C – This vitamin, also called ascorbic acid, supports the immune system, is an antioxidant, and helps maintain many healthy body tissues. Rats make and store their own vitamin C, so they do not need a daily source of it as humans do, so deficiencies are rarely seen. Some of the best food sources of vitamin C are bell peppers, parsley, dark green vegetables, mango, berries, asparagus, and citrus.
Vitamin H – This nutrient works in metabolism, as well as for healthy skin and hair. Vitamin H is also known as biotin, and can be obtained from rice, nuts, barley, oats, mushrooms, and some meats. This is also one of the vitamins that rats absorb more fully through coprophagy.
Vitamin D – This is a fat-soluble vitamin that is required for healthy bones and joints. Food sources include eggs, salmon, butter, liver, and some dairy products. Vitamin D is necessary for the absorption of critical minerals.
Vitamin E – Another fat-soluble vitamin, it can be found in nuts, wheat germ, soy, dark leafy greens, sweet potato, and coconut. Vitamin E is necessary in the repair of tissues, and it protects red blood cells and unsaturated fatty acids from oxidation.
Vitamin K – An important fat-soluble vitamin, it aids in proper blood function and bone calcification. Some foods it can be found in are kale, spinach, tomatoes, broccoli, and soybeans. This is also one of the vitamins that rats absorb more fully through coprophagy.

Minerals too, have just as much importance as vitamins, and they often work synergistically to provide the body with optimal nutrition. The following chart outlines the major minerals in the same way as the vitamins were done, with a bit more information following.

Calcium – This is the most abundant mineral in the body, and it is important for a vast number of processes in the body. Nerve impulses, enzyme reactions, cell structure, and bone formation are just a few. Food sources include tofu, dark green vegetables, and nuts.
Magnesium – The primary function of this mineral is enzyme activation, but it is also involved in bone formation, kidney health, muscle function, hormones, and energy production. Food sources high in magnesium are nuts, some whole grains, molasses, and corn.
Phosphorus – This mineral is essential for the strength of bones and cells, and also activates the B vitamins and major biochemical reactions in the body. Nuts, soy, and even fast foods, are high in phosphorus.
Potassium – Foods rich in potassium include salmon, bananas, and cauliflower. This mineral is needed for fluid balance, nerve, muscle, and kidney function, and energy production.
Chromium – Found in beef, cheese, grapes, and whole grains, chromium controls levels of cholesterol and fat in the blood, as well as boosts resistance to infection. Chromium, with recent research, has been shown to increase the lifespan of domestic rats. It reduces blood glucose levels, essentially preventing damage to certain body proteins. To appropriately dose your rat, multiply its weight in pounds by 189. The maximum dose that can be given is found by multiplying that weight by 227. You can find some excellent recipes for treats using chromium here.
Copper – This mineral is involved in energy production, has antioxidant properties, hormone regulation, and blood, immune, and muscle function. It is also essential for certain vitamins and minerals to be absorbed. Foods it can be found in are crab, yeast, nuts, olives, and tuna fish.
Iodine – Iodine is responsible for proper thyroid function, as well as the proper development of the nervous system. It can also protect against the toxic effects of radioactive materials. Food sources include cod, yogurt, and salami.
Iron – Used in the formation of blood, iron prevents anemia and aids in immune and enzyme function. It also serves as an antioxidant and anticarcinogenic, and can be found in foods like molasses, seeds, cocoa powder, and tomatoes.
Molybdenum – This mineral is essential for the metabolism of several other minerals, and protects against anemia, infertility, cancer, and free radicals. Food sources include cauliflower, seeds, peas, garlic, and pasta
Manganese – This essential trace mineral is used for glucose metabolism, muscle, hormone, and cell function, and is an antioxidant. It is also needed for proper balance related to the inner ear. It is found in peas, barley, berries, and spinach.
Selenium – Found in seafood, whole grains, garlic, and mushrooms, this mineral supports the immune system, as well as improves liver, thyroid, and sexual function. It protects against heart, skin, and eye disease, and is involved in detoxification of tobacco, alcohol, and drugs.
Zinc – This mineral is found in every tissue of the body and has roles in structure, regulation, energy, and metabolism. It is essential for growth, hormones, wound-healing, and detoxification, and is an antioxidant. It can be obtained from ginger, crab, nuts, whole grains, and turnips.

This does not, by any means, exhaust the function of vitamins and minerals in the body. Not only does each have its own properties, but they all act and react based on levels of one another. Every metabolic pathway in the body depends on a specific balance and interaction of all these elements. So, you can see why diet is so important in our own lives, as well as the lives we care for. If you are interested in learning more about how these nutrients function, a supplemental article may be available in the near future, or you can email with further questions. However, the information here will provide you with all the basics you’ll need to understand why these elements of diet are important to consider.
It is with this knowledge and the understanding of what a rat is meant to eat naturally that you can now make changes to offer an ideal diet for your own rats. You will need to study and compare the available foods, both packaged and fresh. When it comes to commercial diets, one must learn how to read the ingredient label and know what to look for. More importantly, you must know what you don’t want to see on the label. If you don’t know what something is, take the time to look it up and find out before feeding it to your pets. After all, if you wouldn’t eat it, you shouldn’t be giving it to them!

Available Diets
With so many commercial diets available, sometimes the easiest place to start is with those that are already formulated and packaged for you. Looking at them will give you ideas of how to compare, as well as to ideally later offer your own rat diet. I say this because it is always best to choose fresh, whole foods over any processed food as long as you balance the diet properly. This goes for us and other pets, as well. The first thing you will learn when studying labels, if you take the time to read them, is that the majority of store bought rat diets are chuck full of filler material, cancer causing chemicals, insecticides, unnecessary dyes, and way too much ground corn. Commercial mixes will often be primarily seed mixes, which are much too high in fat, and if fed as the staple diet, you will likely find that your rat is just eating its favorite parts, so is not receiving the balanced nutrition that the label may claim! I know it sounds harsh, but it’s true, and if your rat’s health is top priority, it is important as well.
Lab blocks tend to be one of the main staples in a rat’s diet, so learning how to look for a quality one is essential. Harlan Teklad is one of the largest producers of laboratory rodent diets. The company states that their diets “provide uniform nutrition” and they are “designed to minimize the nutrient variances” that would occur if feeding varying diets. Well, this is true, but one must only look at nature and how a rat would eat in the wild to realize that the varied diet is exactly what a rat needs. Our pets at home need variety and fresh, whole foods. They are not part of a laboratory that needs fixed nutrient contents to keep studies and analysis numbers consistent. What they need is much more than Harlan Teklad can provide. This is not to say that providing a lab block along with other foods is bad. Some lab blocks do offer the balanced nutrition your rat needs. But, watch ingredients, not brand names.
Typically, Teklad Global Rodent Diets have the first three ingredients as wheat and corn products. Ideally, if a block is fed to females, the main ingredient should be soy. The only Teklad diets to use soybean meal as the primary grain are #8604, #8640, and #8664. But, with higher soy, comes higher protein. And, the current thinking is that low-protein diets are especially recommended for older male rats. So, watch protein and fat levels along with ingredients to tailor to your rat’s specific needs. Teklad diets do use soybean oil as a source of fat, though, which is a highly digestible source of energy. Soybean oil supplies all three omega fatty acids (linoleic, linolenic, and oleic) and antioxidants. The Teklad diets are also free of fish meal, which eliminates nitrosamines. These are things to keep in mind when looking at a lab block. A lab block’s main advantage is that you can be sure the rat is getting balanced and adequate nutrition since it cannot pick out favorite parts. However, you should still offer fresh fruits and vegetables for variety if you choose to stick with a lab block as your rat’s staple diet. As a side note, one lab block I personally have used is the LM brand. It has soy and wheat as its first ingredients, and is surprisingly inexpensive. And, my rats actually eat it, which is nice as well!
As an alternative to the traditional lab block, there are some companies that are spicing it up a bit, and looking towards natural foods and healthy ingredients to feed rodents. One such company is Oxbow, the producer of Regal Rat. It also prevents the selective eating as with lab blocks, and is seemingly more committed to providing overall care beyond minimal dietary requirements. There is no corn in Regal Rat, and the primary grains used are whole brown rice, oat groats, wheat, and soy. The only downfall of this product is that it is only appropriate for rats that are at least 4 months old.
Often, you will hear high quality dog foods can be substituted for lab blocks or Regal Rat. Although this is easily another article in itself and is debatable, let me tell you what I know of the pet food industry, having worked directly in it on several levels. Two of the brands I’ve heard suggested are Iams and Science Diet, the two diets I would never recommend you purchase for, let alone feed, to any animal. Both companies are notorious for their inhumane animal feed studies, but if that does not bother you, then just look at the ingredients. Ground corn, plastics, milling throwaways, and meat byproducts, as well as chemical preservatives are all over the place. Bad choice! I have also heard Nutro Natural Choice Lite as an option. Although, ingredient wise, this is a much better choice, it should only be given in moderation because lamb as a staple in the diet is too high in minerals and cannot be utilized and efficiently excreted from a rat’s body. If you really want to include a kibble, try Nature’s Recipe Vegetarian Formula or Natural Balance Vegetarian. Both contain highly digestible whole grains, without the need for byproducts, fillers, dyes, or sketchy preservatives. In fact, Nature’s Recipe also makes a vegetarian canned diet and crunchy treat. Both of these can be excellent additions to your rat’s diet. They are much more suitable to your rat’s dietary needs. Even if you choose these, the lab blocks, or the Regal Rat, you should still offer fresh foods daily to complement the staple portion of the diet. Keep in mind if you choose to use a dry dog food, you must be very cautious to get a proper balance of vitamins and minerals, as well. In general, formulations for dogs do not make a good substitute for rat food because rats have very different dietary needs. Therefore, although there are suggested dog food products to use, it is only ideally to use as a supplement to the main diet or to be given as treats.
This brings us to the other types of commercial diets, which includes the many choices of mixes. There are some that are definitely better than others, but keep in mind that if you choose this as a staple diet, and your rats eat selectively, they will not get all the nutrients that the food is designed to provide. Supplementing with fresh, healthy foods is therefore very important for adequate nutrition here too. When looking at different rat mixes, the first things to look for (and avoid) are the typical rabbit pellets and corn. The pellets are basically empty filler and better used as bedding for your rats than food! Ideally, the pellets and corn should not be the main ingredients, and if they are, they should not be the first, and should be well balanced with other whole grains. Some of the mixes out there are almost more appropriate to feed along with your own staple diet rather than fed as the sole source of nutrition. This is because there are some elements of a select few of the mixes that are good to get into the diet. Some may even be used as a treat. Two of the mixes that are of higher quality are Brown’s Second Helping for Rats and Supreme’s Reggie Rat. Both do have corn, but not as a primary ingredient, and they have a diverse blend of other whole grains, vegetables, fruits, nuts, and seeds. Brown’s also has probiotics in its formula. There are no chemical preservatives in either diet. One other that has probiotics and some of the properties of Brown’s and Reggie Rat is Small World’s Select Blend Mouse & Rat diet. However, this diet does have corn as a primary ingredient. Personally, I have not encountered any other mixes that are suitable for feeding to pet rats if health and longevity are primary goals. Check the ingredients and make sure you know what you are giving your rats, and I am confident that you will discover the very same thing.
Label checking should also extend to treats, so watch out for high amounts of sugars, dyes, chemicals, byproducts, fillers, and artificial preservatives. Use some of the examples in this article of healthy, real foods to feed your rats for treats instead. Remember that your rat’s diet includes the treats, and you do not want to counteract an ideal diet with treats that do the opposite in the way of health. In fact, as a treat, you can even share a bit of your dinner with them each night. Make sure and follow the general guidelines here for what you can feed your rats, and you may find yourself eating healthier too by sharing your meals with them!

Making Your Own
Believe it or not, a homemade diet, if done properly and with the proper guidance, can be nutritionally sound and better for your rats than what you can buy at the local pet store. First of all, it is important to understand that you should only undertake the making and offering of your own diet with the assistance of a vet or nutritionist because coming up with the proper balance of nutrients is important for your rats. If you make up a large batch of food all at
one time, there really isn’t a whole lot of effort involved in making your own diet either. Besides, when it comes to a healthy, long life for your rats, it is all worth it! The benefits of feeding fresh, whole, raw (ideally organic) foods are immeasurable!
If you choose to offer your own diet, you need to be sure that your rats get all the nutrients they need. A staple or base is often used to ‘play it safe’. A lot of people find this is most easily accomplished by feeding a lab block or high-quality rat formula, like Oxbow’s Regal Rat, along with your own mix and fresh foods. In a situation like this, the blocks should make up at least 80% of the diet; and you need to make sure that your rats are not just picking out the other parts or they will not be getting all their necessary vitamins and minerals. There are lots of choices out there for lab blocks if you choose to feed them over the Regal Rat, so exercise caution and read labels to be sure you know you are getting the best quality ingredients and not defeating the purpose of feeding a more natural diet. If using lab blocks, I personally recommend purchasing from LM Animal Farms; but there are other suitable blocks depending on availability and rat preference.
There are also very specific homemade formulations by experts in rat care that cover all the basics without the need for the additional vitamins and minerals from commercial diets. The best of these diets, and the only one I recommend, was developed by Debbie Ducommun. It is commonly known as the Rat Fan Club Diet. It is one of the most ideal diets, not just because of ingredient quality, but because of complete attention to nutrient detail. The nutritional value of the diet does depend on you following all of these details to the letter. Therefore, it is a bit more complicated until you get into a system for having all the fresh foods and main mix ingredients on hand. In the end, it is well worth the effort. This main mix and fruit/veggie diet can also be used as the 80% or more portion instead of lab blocks or Regal Rat when feeding it along with your own mix as stated above.
The Rat Fan Club Diet is a tofu-based main mix; and specific, supplemental fresh foods. The main mix ingredients are as follows: 1500 mg calcium (from chewable tablet), 2000mcg chromium picolinate, 50mcg vitamin B12, 40mg manganese, ¾ cup crushed Total cereal, 4 tsp raw sunflower seeds, 1 Tbsp flax seed, 3 Tbsp raw oatmeal, 4 tsp pearled barley, 4 tsp millet, 3 Tbsp cooked brown rice, 4 Tbsp toasted wheat germ, 2-¼ Tbsp nutritional yeast flakes, 2 Tbsp blackstrap molasses, 1 lb. soft tofu. Approximately 3 Tbsp of this mix should be fed daily for a 1-lb rat. The mix will need to refrigerated and should be used within 1 week. Along with the mix, you are also required rotate in particular fruits and vegetables, as well as liver and oysters, to complete the diet. The weekly calendar below shows how to include these fresh foods. The first two rows are required for adequate nutrition, but the second two are only suggestions and can be changed to include other fruits and vegetables that you may have on hand. Later in the article, there are other recommendations for some fresh foods that are particularly healthy to include in your rat’s diet, as well as some that should be avoided. For this and other diets, serving sizes of fresh foods for a 1-lb rat are as follows: 2 tsp cooked beans, ¾” cube cooked sweet potato, 1-½”  broccoli floweret, 2” square of leafy greens, 1” square of most vegetables, ½” cube fruits, 1 oyster, and ¾” cube cooked liver. For any questions or further details about the Rat Fan Club diet, please visit www.ratfanclub.org.

There are also other homemade mixes that have been used by many over the years. However, none are analyzed and formed as nutritionally complete as the Rat Fan Club Diet. Some of them can still, however, offer a healthy and tasty supplemental mix (20% or less of the main diet). They have lots of room for personal adjustments using the information you now have on a rat’s dietary needs.
One of the other mixes is known as Suebee’s. There are many variations on this diet, and it tends to be one of the most popular ones with those that make their own food because of its flexibility. Please remember, though, that this is not a diet meant to be fed as the sole source of nutrition. This is because the Suebee’s is NOT a nutritionally complete diet, as it is lacking in copper and calcium just to name a couple. To feed this type of grain mix diet to your rats, feed it in combination with the staple portion (80% or more) and a variety of fresh foods. Recall that the staple portion of the mix (80%) is Oxbow Regal Rat, high-quality lab blocks, or the Rat Fan Club Diet. Although the original Suebee’s accepts Nutro Natural Choice Lite Dog Food as the staple portion, it is not recommended or suggested by nutritionists. The original grain mix ingredients are itself includes 1 lb. puffed wheat, 1 lb. puffed rice, 1 box Total cereal, ¾ lb. rolled oats, ½ lb. unsalted soy nuts, ½ lb. dried fruit, ½ lb. dry pasta, ¼ lb. sunflower seeds, and ¼ muesli. Although there is some grain variety in this mix, there is some conjecture over feeding puffed grains because the puffing process creates unhealthy compounds. Therefore, it is recommended that if one uses this mix, the amount of puffed grains should be reduced or eliminated and replaced by whole grains like wheat berries or cooked brown rice.
There are also modifications that try to reduce the possibility of selective eating by eliminating different textures and shapes that are easily picked out. One example uses the following for the grain portion: 1 cup each of whole-wheat flakes, triticale flakes, rye flakes, barley flakes, spelt flakes, soy flakes, kamut flakes, oat groats, toasted buckwheat, ½ cup each of flax seeds and sesame seeds, and ¼ cup each of sunflower seeds and pumpkin seeds. A downfall with this is that the whole food concept is somewhat lost here as you are using a majority of processed foods. Remember that this is to be used only as 20% or less of a rat’s diet with the other 80% being a nutritionally complete product.
One other diet that should be mentioned is from the Rat and Mouse Club of America. It and the others above will start to give you ideas for what to put in your own homemade concoction! The RMCA diet’s grain portion is made up of 2 cups Cheerios, 2 cups Grapenuts, 2 cups oats, ½ cup sunflower seeds, and ⅔ cup unsalted soy nuts. Already, you can see that this diet does not offer much in the way of grain variety, though. You are relying again on processed cereals; and in this case, these cereals also contain sugar. This diet does at least address some missing vitamins, including K, which needs to be added. To every 50g of this diet, you will need to add 250mg calcium, 2.5mcg vitamin B12, 50IU vitamin D, and 50mcg vitamin K. If you can’t find a vitamin K supplement, just feed 1 small steamed Brussels sprout daily. For any homemade grain mix, vitamins can be additionally supplied using fresh fruits and vegetables. For any homemade grain mix, vitamins can be additionally supplied using fresh fruits and vegetables. Review those ideas in the charts above or in the list below for healthy options.  A rat can eat a third of its own body weight in a 24-hour period; so not only is it important to regulate what your rats take in, but it also gives plenty of opportunity to combine and rotate some of the ideas in this article.
Understanding the importance of having these fresh foods is vital no matter what you use for your main rat diet. Remember that the processed, devitalized foods found in your local pet store are lacking natural enzymes and healthy bacteria, which your pet needs for a healthy immune and digestive system. In fact, including healthy bacteria in the diet in the form of yogurt and cottage cheese is ideal. Other food supplements that are great to include in your rat’s diet are fish oil, kelp, flax, honey, molasses, apple cider vinegar, wheat germ, oatmeal, applesauce, cooked rice, etc. Feeding fresh, whole foods in this manner helps reduce the risk of disease as your rat ages. It is important to also include fresh fruits and vegetables to provide vitamins, minerals, anti-oxidants, and phytochemicals to prevent disease and to slow the aging process. Usually it is best to feed foods "as is" since cooking destroys enzymes inherently found in raw foods. There are some exceptions to this, though, and you can use yourself as a model for what may need to be cooked prior to serving. The choices of fresh foods are just as endless as those that are available for people. Remember to clean fresh produce well to remove as much of the surface pesticides as possible. Better yet, buy organic for yourself and your rats!
Fruits, although they should be offered every day, should be given in slight moderation compared to the fresh vegetable portion. The natural sugars in fruit are nutritionally similar to starches, though, and are very important to the overall diet. Some options can even have secondary health effects. Bananas, plums, prunes, and raspberries have antibiotic properties. Cranberries, strawberries, plums, and prunes have antiviral properties. For arthritis, dates work well. Red grapes and blueberries have excellent antioxidant properties and are good for fighting against cancer. Prunes are also good for stroke prevention because of their anti-inflammatory properties. Most any fruit is good, but male rats should not have orange juice or orange pieces that include the rind. In the oils of citrus, there is d-limonene, which can cause kidney damage and cancer as it reacts with a unique protein in the kidney of male rats. Green bananas should not be fed either as they inhibit the digestion of starch.
Vegetables should be offered in 2-3 servings per day, and the list of possibilities is endless! Just as it is true for fruits, many vegetables also have special health-related properties. Eggplants and garlic have antibiotic properties. Broccoli is an antioxidant. Celery is good as an anti-inflammatory. Most vegetables are fine to feed with very few exceptions. Some may need to be cooked to be given to rats as well. For instance, green potato skin and eyes contain a toxin, solanine. There are, however, some myths about certain raw foods though. Feeding raw sweet potatoes or artichoke is okay, for example. However, you will likely find that your rats prefer them cooked anyway! There are also some foods that can be fed, but should only be done so in moderation. Raw, red cabbage and Brussels sprouts are healthy in limited amounts, but they can have a toxic affect if fed excessively. Spinach, beets, and Swiss chard, as well as some others in the same family, are high in oxalates, which can contribute to urinary and kidney stones in those prone to them. Dry corn has high levels of nitrates and amines. They combine during digestion to form nitrosamines, which are essentially carcinogens. Dry corn can also contain fungal contaminates that are a leading cause of liver cancer. This is another reason why corn, unless quality or source is determined, should be avoided for the most part in commercial diets.
Some cooked legumes and herbs also have special properties. Tea, mustard, and garlic have antibiotic properties. Fish oil, ginger, garlic, and clove tend to work well for arthritis. Soybeans are antioxidants. Parsley, fish oil, and flax are great for stroke because of their anti-inflammatory properties. There are also some foods in this category to avoid as well. Raw beans and peanuts destroy vitamin A and can cause red blood cells to clump, as well as inhibit the digestion of protein and starch. Other cautioned ingredients include carbonated drinks since rats can’t burp. Chocolate, especially dark, in small amounts is okay and can even act as a mild bronchodilator in rats with respiratory problems. As with any refined sugar, the rule is to not go overboard.

Special Considerations & Notes
Special considerations sometimes need to be made depending on health conditions and age. For instance, if a rat has heart problems, it is essential that the diet is low in sodium. In this case, a soy-based lab block, along with fresh fruits and vegetables, would be the ideal diet. Dairy, cereals, salts, and baked foods should be avoided. For rats under 4 months of age, and those that are pregnant or lactating, there is a need for increased fats, proteins, and specific vitamins and minerals. Be sure to take these things into consideration when preparing your rat’s diet.
As a side note, it is essential for your rats to always have access to fresh, clean water. Check water bottles daily to be sure they are full and working properly. The best diet in the world means nothing without the availability of fresh water. If you are having trouble with a leaking bottle, remember that they must stay airtight to work. This means the fuller the bottle is, the less air, the tighter the seal. If you really no longer want to mess with leaky bottles, order a Water Buddy from SMRF. They will not leak because they use a valve rather than the stainless steel balls. These bottles are made of PVC, though, and will need to be cleaned and have the water replaced a couple times per week to prevent any chemicals from leaching into the water. The quality of drinking water is often disregarded when it comes to diet. However, city tap water often contains fluoride, a carcinogen. The best choice is quality, bottled water for your rats; but check with the company to make sure the water is fluoride-free. Not all bottled waters are!

Conclusion
As you can see, preparing a homemade diet does take quite a bit of information if you want to do it right. The health of your rats should be worth it though. A world of difference can be made to your animals by following the general advice laid out here. The benefit of feeding in this way to rats, other pets, and ourselves will make an impact in future health and wellbeing. If you take the time to study these ideas, you will find that it is worth every bit of effort you put into it. Your rats will thank you the rest of their long, healthy lives!

References available upon request. A huge thank you to Dr. John VanDaele, Dr. Virginia Leis, and Debbie 'the Rat Lady' Ducommun. Your guidance and assistance with this project was beyond measure! A big thanks also to Sandy Dittmer for her proofing/editing expertise on the majority of this document!

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