trying to quit smoking.

[Fleet Admiral Zapington]

Sisha is unhealthy? That depends what you're smoking in it, I don't think smoking herbs is "very unhealthy".

Breathing burned plant matter (smoke) is and will always be unhealthy for your lungs and throat.

Explained;

The smoke from burned plant matter contains Polycyclic aromatic hydrocarbons (PAH), some of which are;

Spoiler :

acenaphthene
acenaphthylene
anthracene
benz[a]anthracene
benzo[a]pyrene
benzo[e]pyrene
benzo[b]fluoranthene
benzo[ghi]perylene
benzo[j]fluoranthene
benzo[k]fluoranthene
chrysene
coronene
dibenz(a,h)anthracene
fluoranthene
fluorene
indeno(1,2,3-cd)pyrene
phenanthrene
pyrene

These are Carcinogens and will cause cancer in the long run. The same particles can be found on grilled meat.

PAHs toxicity is very structurally dependent, with isomers (PAHs with the same formula and number of rings) varying from being nontoxic to being extremely toxic. Thus, highly carcinogenic PAHs may be small or large. One PAH compound, benzo[a]pyrene, is notable for being the first chemical carcinogen to be discovered (and is one of many carcinogens found in cigarette smoke). The EPA has classified seven PAH compounds as probable human carcinogens: benz[a]anthracene, benzo[a]pyrene, benzo[b]fluoranthene, benzo[k]fluoranthene, chrysene, dibenz(a,h)anthracene, and indeno(1,2,3-cd)pyrene.
PAHs known for their carcinogenic, mutagenic and teratogenic properties are benz[a]anthracene and chrysene, benzo[b]fluoranthene, benzo[j]fluoranthene, benzo[k]fluoranthene, benzo[a]pyrene, benzo[ghi]perylene, coronene, dibenz(a,h)anthracene (C20H14), indeno(1,2,3-cd)pyrene (C22H12) and ovalene.