The weakness could be for one of the following reasons:

1. Cleansing. Generally, if you feel low energy in the first few days or weeks following a switch to a vegan diet, it may be because of a cleansing action of the body. Animal-source protein, like sugar, alcohol, tobacco and other drugs, is addictive. When you stop it there are withdrawal symptoms followed by cleansing. This is akin to smokers who start coughing only when they stop smoking. This is because the body does not waste energy cleansing as long as it sees that the toxic substance is regularly consumed. Depending on how unhealthy the earlier diet was, the withdrawal period could be shorter or longer after which energy levels should rise and a sense of wellbeing should ensue.

2. Vitamin B12 deficiency. If the weakness starts after several months or years of changing the diet, you may be suffering from a nutritional deficiency, most probably a B12 deficiency (it is difficult to suffer from a protein or iron deficiency if you are eating a variety of whole foods) A simple B12 supplement, in addition to adding a regular serving of dark green leafy vegetables or a fortified source of B12, like fortified soy milk, to your diet may relieve your symptoms. Some people are unable to absorb B12 in which case they may need injections of B12. Others have low levels due to alcohol, tea and coffee. It’s a good idea to have annual check-ups for Vit B12 levels.

3. Too many medications. Many people don’t understand the power of a whole vegan diet. As we start getting better, even the medications which have been prescribed for life become unessential. Too much medicine makes us feel low, especially when they are not needed. For example, if the blood sugar or blood pressure drops, the only answer is to reduce medications.

This is why we always advise tests before and 3 months after making dietary changes. This way one can be sure that things are improving and should consider cutting medications. Of course, in the case of diabetes and hypertension one does not even have to wait this long. It’s easy to check blood sugar and blood pressure at home. It does not matter if these methods are not 100% accurate. They are accurate enough to get a picture of what is happening to the body. Do not be too slow in cutting down medications, under medical advice.

4. Vitamin D deficiency due to lack of exposure to sunlight. This can lead to depression, joint problems, diabetes, sleep disturbances. Important to check Vit D levels and if needed supplement.