Acne is reported to be less common in people that have a diet with lower glycaemic index, eg, natives from Kitava and Papua New Guinea, the Ache people of Paraguay, Inuits and rural residents of Kenya, Zambia and Bantu. These people tend to become sexually mature at a later age than in the cities where higher glycaemic index foods are consumed. Early puberty is associated with earlier onset and more severe acne that tends to peak at the time of full maturity (age 16 to 18).
The exact cause of rosacea is still unknown. The basic process seems to involve dilation of the small blood vessels of the face. Currently, health researchers believe that rosacea patients have a genetically mediated reduction in the ability to dampen facial inflammation that is incited by environmental factors such as sunburn, demodicosis (Demodex folliculorum in the hair follicles), flushing, and certain medications. Rosacea tends to affect the "blush" areas of the face and is more common in people who flush easily. Additionally, a variety of triggers is known to cause rosacea to flare. Emotional factors (stress, fear, anxiety, embarrassment, etc.) may trigger blushing and aggravate rosacea. Changes in the weather, like strong winds, or a change in the humidity can cause a flare-up. Sun exposure and sun-damaged skin is associated with rosacea. Exercise, alcohol consumption, smoking, emotional upsets, and spicy food are other well-known triggers that may aggravate rosacea. Many patients may also notice flares around the holidays, particularly Christmas and New Year's holidays.
Birth controls can affect hormone levels, and some women may be finding that their birth control is causing acne due to increases in sebum production. This rise in sebum can affect the skin, clogging up pores and leading to acne. According to The Huffington Post, birth control pills that contain androgen-based progestin have been indicated as the most likely offender.
Sun exposure is a well-known flare for many rosacea sufferers. Sun protection using a wide-brimmed hat (at least 6 inches) and physical sunscreens (like zinc or titanium) are generally encouraged. Because rosacea tends to occur in mostly fair-skinned adults, physicians recommend the use of an appropriate daily SPF 50 sunscreen lotion, along with overall sun avoidance.
Don't Squeeze, Pop, or Pick at Pimples: Pass up the temptation to pick or squeeze a pimple. Doing so can force debris deeper into the dermis, spreading an infection to other tissue and worsening inflammation. This is especially true for deep, serious blemishes like nodules and cysts. Remind yourself that popping pimples can extend the healing time and ups the chance of it leaving a permanent scar. Allow the blemish to heal on its own. If you've already picked at a blemish, take steps to help heal it and minimize skin damage.
Exfoliating cleansers and masks: A variety of mild scrubs, exfoliants, and masks can be used. These products may contain salicylic acid in a concentration that makes it a very mild peeling agent. These products remove the outer layer of the skin and thus open pores. Products containing glycolic or alpha hydroxy acids are also gentle skin exfoliants.