Your body is a living machine with lots of different parts working together.
        
Included are hormones, which are special chemicals your body makes to help it do certain things. They are most noticeable in the body when it begins developing into it's adult form. During this time, it’s fully loaded with hormones that tell the body it's time to start changing.
              
Hormones, or you could say, 'chemical messengers', travel to different parts of the body and affects just some of the following:  bone density, sleep cycles, appetite, heart function, growth and reproduction, mood, metabolism, temperature control, fluid balance, blood sugar control, etc...
             
Getting enough sleep, exercising and a good nutritional plan are some of the most important factors in balancing hormones. 

      

             

Now for lashes, the hormone estrogen in the body affects their rate of growth and their thickness. The right levels of estrogen will grow thick and healthy hair whilst low levels of estrogen can lead to thinning hair. The levels of this hormone can fluctuate depending on a number of different factors. For instance, during pregnancy, the enhanced supply of the hormones estradiol and progesterone increases the number of hair and lashes in the anagen (active growth) phase.
                  
However, in some particular lash serums, there may be chemicals present which fall under the term 'prostaglandins'.

These were originally found in eyedrops used to treat glaucoma. However, some brands began producing lash serums with this chemical included when one of the noted side effects of this treatment was longer lashes. This chemical is now banned in lash serums as other side effects include 

• Permanent darkening of the eyelid(s)
• Permanent discolouration of the iris - usually from blue to brown.
• Itchy, swollen, red eyes
• Watery eyes
• Blurry vision
• Red or brown circles under the eye
• A sunken eye appearance

             

The following ingredients are all types of prostaglandins (both natural and synthetic) that you might want to avoid:

• Isopropyl Cloprostenate
• Isopropanol Phenyl-hydroxy-pentene Dihydroxy-cyclopentyl-heptenate
• Bitamoprost
• Dechloro Dihydroxy Difluoro Ethylcloprostenolamide