For a star like the Sun, about 20 percent or so of its hydrogen will get 'fused' into helium nuclei as nuclear 'ash'. So, this works out to 0.20 x 4 x 10^33 grams = 8 x 10^32 grams.
As a star continues to burn hydrogen into helium during its' main sequence' phase, it will actually become brighter with time.
The Sun will be 10 percent brighter in about 1 billion years, and after 6 billion years its brightness, or luminosity, will swell to over 100 times as it becomes a red giant star.
Copyright 1997 Dr. Sten Odenwald
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