Yang deficiency and yin deficiency affect different parts of your body, and the symptoms of deficiency vary. To begin, let's take a look at some symptoms when yang energy level is low. They are:
-- a recurrent infections with colds that never seem to clear
-- a tendency to "catch everything around";
-- Impotence (due to weak kidney yang),
-- digestive upsets associated with weak spleen yang
-- heart problems caused by deficient heart yang.

As for yin deficiency, the symptoms include:
-- night sweats,
-- sleeping problems,
-- an unnatural flush of the face
-- the pulse is likely to be fast and is described as "thready".

The Yang Deficiency Syndromes
Yang is associated with active energy and fire. Therefore, a deficiency of yang energy leads to a lack of these sorts of characteristics. Tiredness and feeling cold are often signs of this problem. It is important to ensure that the problem really is one of yang deficiency, and not to mix up with signs of excess yin. To address this deficiency, the Chinese medicine therapy will focus on warm and tonifying remedies using herbs that are intrinsically hot.

The Yin Deficiency Syndromes
Yin is associated with quiet and passivity. Therefore, in yin deficiency, these symptoms are diminished. This can create an appearance of apparent yang activity or excess heat symptoms: restlessness, reddish complexion and tongue, and feeling warm or hot and feverish. Yin deficiency is often chronic and can be difficult to diagnose quickly or accurately.