Fasting Your Cat or Dog

Before processed pet foods became commercially available, most domestic pets were fed a more basic and down to earth home-made diet. Feeding was essentially based on the concept of natural rearing. This involved feeding raw meats, cereals, vegetables and adding herbal supplements. Part of the natural rearing regime involved fasting, which was carried out on a regular basis. Fasting was considered good for general health and could even help recovery during illness by enhancing the immune system.

Buster Lloyd-Jones, the founder of Denes, was a great advocate of both natural rearing and fasting, using these methods to help many of the animals he treated during his lifetime. He realised that fasting had a number of positive benefits, which could be used to great advantage alongside his diets, supplements and herbal remedies.

The idea of fasting may seem quite strange to most of us, but simply mimics the behaviour of animals living in the wild. Food would not always be available and even the best hunters would not be able to find or catch food every single day. In fact, it would be quite normal to go for one or two days each week without eating. Similarly, sick animals would probably be unable to catch food or would simply not feel like eating. This enforced break would allow the digestive system to have a rest, during which time the body could concentrate on healing and repair.

Fasting essentially allows the body to unload accumulated waste products, such as toxins that have been stored in the liver and the fat reserves over a period of time. In addition, fasting also provides an opportunity for tissues to repair and regenerate, enhancing both health and digestion. The overall effect is to help restore the natural balance of the body. This will also go some way in preventing chronic health problems, such as skin, joint and heart conditions and can result in a fitter, brighter and more alert animal. Fasting also helps prevent obesity, as fat reserves are burnt up during fast days. It can also be included as part of the overall treatment for some chronic conditions, such as skin problems, and can also help with breaking a fever.

If you plan to fast your cat or dog on a regular basis, then ideally you should try to do this at least once every month. Otherwise, try fasting whenever you feel that your cat or dog needs a boost or if they have a condition that would benefit from a period of fasting.


Most cats and dogs can be fasted. The actual fasting process is not so difficult to implement and involves three basic stages. It is not a good idea to fast very elderly animals, young growing puppies and kittens and pregnant bitches or queens. Animals with liver and kidney problems should not be fasted without veterinary guidance.

  • The first phase involves feeding smaller amounts of normal food, preferably nothing too rich and including some vegetables. These should be cooked (preferably steamed) and finely diced, although raw carrot can be grated and added directly to food. Do this for two or three days, gradually feeding smaller amounts each day.
  • Phase two involves changing to a liquid only diet. Ideally, this should only be filtered or bottled water, avoiding tap water because of the impurities. If this stage proves difficult then you can use vegetable juice or vegetable broth instead for dogs or weak fish broth for cats. You can also add honey to the water if you wish. This is especially useful for weaker animals. Cats will need to be kept in at this point or they may go in search of other food sources. The liquid fast should take place over a period of 24 to 48 hours. If you don’t already dose with Denes Respiratory Support Capsules, then these should be given during the fast period as Garlic is a natural disinfectant. If the liver is particularly overloaded with toxins then Denes Liver Support Powder can be added as well and given over a period of 10 days or so. You can also use homeopathic remedies to help clear out toxins. Denes Nux vomica 30c is ideal and can be given twice daily for a few days. Alternatively Aloe Vera is also useful in helping to detox the body especially where constipation is a problem
  • The last phase involves breaking the fast by adding in solid food again. Feed small amounts at first, increasing the quantities over a period of two or three days until you are feeding normal amounts again.