Lesbianism is sexual activity or attraction between women. Female homosexuals are often called lesbians (after the Greek island of Lesbos, home of Sappho, the poetess of Lesbos). Women who are attracted to both women and men are called bisexuals.
The first known written usage of the word "lesbian" in the sense meant here dates only from the 19th century. Earlier uses of the word from as far back as the 17th century, can be found but used in an entirely different sense. Lesbianism is also called sapphism or female homosexuality. (Sappho penned love sonnets to women. She lived from 610-580 B.C.)
In 1997, the National Breast and Cervical Cancer Prevention Program included lesbians as a priority population.
In the United States, estimates of lifetime same-sex behavior among women are 8%–20%, and 1.4%–4.3% of all women may be sexually active with other women. An estimated 2.3 million women describe themselves as lesbian. In its 1999 report, Lesbian Health: Current Assessment and Directions for the Future, the Institute of Medicine emphasized that more data on sexually transmitted infections (STIs), Pap smear screening, and risk for cervical cancer in lesbians were needed.
Lesbianism and Health Issues
For more information please see: Lesbianism and Obesity
In regards to lesbianism and obesity, in April of 2007, the American Journal of Public Health analyzed data from 2002 National Survey of Family Growth and the data suggested that American lesbian women were 2.69 times more likely to be overweight and 2.47 times more likely to be obese than all other female sexual orientation groups.  The abstract for this study indicated that "lesbians are at greater risk for morbidity and mortality linked to overweight and obesity." 
In 2009, the PubMed article abstract for a Polish psychiatry journal Psychiatria Polska article declared:
|“||Homosexual women are less concentrated on physical appearance and more satisfied with their bodies while being more tolerant to obesity.... For lesbian women the ideal body image is more massive than for heterosexual women.||”|
In 2007, a purported lesbian wrote to Andrew Sullivan, the political commentator and administrator of The Daily Dish blog:
|“||And - oh heck, I'll admit it - aesthetics have value, too! As a woman, I may not be as focused on looks as men are predisposed to be, but I sure am tired of seeing so many queer ladies out there who are way past 200 pounds. Way, way past. Sorry, but no amount of "fat acceptance" is going to make that a pleasant sight - gay, straight, butch, femme, male or female.||”|
However, liberals assert that lesbians are considered to be amongst the lowest risk groups for some STDs including HIV 
- Lesbianism Encyclopædia Britannica.
- Progress has been made in recognizing lesbians as a target population
- Lesbians and Infectious Diseases
- Overweight and Obesity in Sexual-Minority Women: Evidence From Population-Based Data, Ulrike Boehmer, Deborah J. Bowen, Greta R. Bauer, American Journal of Public Health, 2007 Jun;97(6):1134-40. E pub 2007 Apr 26.