Pharmaceutical Analysis Books for GATE Exam

Supplements are products that provide essential nutrients and as the name implies, are to be supplemented with something else. Their main name is to prevent deficiencies in case of an unbalanced diet or to treat or prevent diseases.
Foods are to be ingested for nutritive, therapeutic and sometimes, aromatic value.
Drugs, however, are used to treat, cure, mitigate, or prevent a disease and/or are intended to affect the structure of the body.
So what are they then? Drugs or food?
This has been one of the most controversial issues in the FDA history. Manufacturers tout the supplement/food angle but the FDA has to look at the drug angle. Many people call glucosamine and digitalis foods and not drugs and this is accepted to be correct around the world.
On one hand, many say that nutraceuticals do not require regulations because they have unreliable benefits (work for some, not for others) and that they are as "safe" as foods. Foods are generally regarded as safe by the government.