Health concerns with henna?

Mehndi, also known as henna, is the powdered form of the topmost leaves of a plant called Lawsonia inermis. This amazing plant thrives best in hot, arid climates with long droughts (I'm surprised it isn't a species of cactus), and the best crops are harvested after the monsoon rains. The powder is mixed with an acidic liquid to break open the cellulose of the plant, and mixed with suitable essential oils to draw out the staining molecule to make it available for designs. This staining molecule (which is one of the most harmless substances on Earth) binds with the protein in your skin, forms an orange stain, and oxidizes to a brownish-red colour over 48 - 72 hours.
My post, "Things you should not do", outlines the chemistry of the reaction.

Is it safe for everyone?

Not really.

The staining molecule, hydroxynaphthoquinone (HNQ) isn't safe for people who have blood disorders, severe anaemia, jaundice, and something known as G6PD deficiency (glucose-6-phosphate dehydrogenase deficiency). In other words, if you're allergic to fava beans, have low iron levels, are allergic to mothballs (I don't use mothballs in my mix! It's just got a very similar structure to HNQ) or not allowed to take medicine containing quinones, then unfortunately, henna is totally forbidden :(
If you do get it done - even a small design - it could be life threatening, and I want you to be safe when considering getting your henna done! Please do a check because as with all things - ask your doctor.
Nobody said you can't have a glitter-and-gems substitute though! ;)

Another topic I'd like to touch on would be the notorious 'Black Henna'. I'm almost certain you've heard of it. No bulk nor substance, stains jet-black in 20 minutes, doesn't even contain traces of henna powder, washes off after an hour to reveal that stain...and then? BAM! Prepare to bid a blistery farewell to your skin. I won't include pictures here but if you do a Google search, I'm pretty sure you'd never consider getting a black henna design done. Ever. Have you always wondered why you aren't allowed to let your skin come into contact with hair dye? It contains dangerous substances, the most dangerous being PPD (1,4-diaminobenzene / p-phenylenediamine), the culprit that paints the town black. It's a confirmed cancer-causing agent. Guess what - unscrupulous henna artists are using those very ingredients to stain your skin! If a henna artist offers black henna (or even instant mehndi - similar concept - starring sodium hydroxide, also known as drain cleaner. Makes your skin peel in places as it fades.)...run for the hills and never look back.

The use of natural mehndi is always the best option. I'd say about 90% of people can safely get it done, and even then, certain skin types, climate, genetics, skin thickness all play a factor in the staining quality.
Thicker skin stains better than thinner skin.
I offer only a natural mix of mehndi, so I'm just a call/e-mail away! Bridal consultations are free, you're more than welcome to let me know anytime when you'd like to come over and test the stain on your skin to ensure that you're satisfied with it.

Henna is never black!