( CNN ) -- When it comes to what she deems the American `` obesity crisis , '' Sarah Varney says , it 's easy enough to focus on the raw numbers : Sixty-nine percent of Americans are overweight , according to the Centers for Disease Control and Prevention , and 35.1 % of those people are obese . In 2008 , medical care costs related to obesity were as high as $ 147 billion , and an obese person 's annual medical bill was $ 1,429 higher than that of a normal-weight person . Varney 's new book `` XL Love : How the Obesity Crisis Is Complicating America 's Love Life , '' out in August , looks at how our increasing girth is weighing on the humans beyond the statistics , particularly the way people relate physically and intimately . Random online match helps man lose nearly 400 pounds . `` I certainly do n't see the obesity epidemic reversing itself any time soon , '' Varney said . `` We 're just beginning to understand how human relationships are being affected . '' During her 2Â½ years of research , Varney found that obesity can have a chilling effect on sexual relationships , from physical barriers to intimacy to attitudinal shifts with weight gain and even loss . Varney became immersed in the topic as a senior correspondent for Kaiser Health News and a contributor to the NPR series `` Living Large , '' which focuses on how obesity is changing American life . The book looks at how obesity is altering sexual development , dating , marriage and sexual function ; how weight loss can make or break a relationship ; and even the lure of plus-size porn . Varney says it took a lot of work to gain the trust of her subjects , many of whom she met through weight loss counselors . They shared highly personal , and often difficult , stories of love lives dramatically affected by weight . They 're people like Dana Englehardt of the San Francisco Bay Area . Readers first encounter Englehardt at her heaviest , 265 pounds , strapped to a CPAP machine for sleep apnea and completely indifferent to her husband , Larry 's , advances to the point where he had stopped trying . `` I just felt so bad about myself . Even though my husband said , ' I love you the way you are , ' I could n't even begin to imagine that that could be true , '' Englehardt told CNN . She said she had a satisfying sex life at 200 pounds , but when she gained 65 more after marriage , later hours at work and unhealthier cooking , `` it just pushed me over the edge . '' Englehardt pops up later in the book after undergoing bariatric surgery for weight loss and encounters an interesting twist : Weight loss did n't solve her sexual roadblocks ; therapy that addressed body image as a whole and marriage counseling did . `` I just thought losing the weight would solve all that . I would n't have all these hang-ups , '' Englehardt said . While the pounds fell off and the clothes got smaller , she says , `` I did n't feel like a small person . '' As she began to reclaim her energy , confidence and sexual desire via the surgery and counseling , she discovered that the learning curve was n't just hers to navigate . `` I did n't know that you were interested anymore , '' Englehardt 's husband , Larry , says in the book . `` And so I had to basically learn , and I 'm still learning , when she 's interested and when she 's not . '' Couple shed 280 pounds and get noticed for the right reasons . `` I do think there is this stereotype that ( the obese ) just shut down , this idea that you go numb and are at war with yourself , '' Varney said . `` But when you go knocking on that door , what you hear are things like , ' I 'm incredibly saddened by this . I desperately want to be in a relationship with my husband or my wife . I want to it to feel good when he/she touches me . ' `` In a chapter titled `` Sex : The Birds and the Bees with Aching Knees , '' Varney moves from the brain to the body , exploring `` bad mechanics '' between partners as well as how belly fat can decrease testosterone production in men , potentially leading to sexual issues . You do n't have to be overweight to experience bad sex or a lack of libido , says one advocate for sex at any size . `` The problem with the assumption that fatness 'challenges ' relationships in some unique way is that it relies on a mistaken assumption that the exact same kinds of body-image issues do not affect anybody who is not fat , '' body image activist Hanne Blank said . Blank has written extensively on sexuality and weight , including books like `` Big Big Love : A Sex and Relationships Guide for People of Size ( and Those Who Love Them ) '' and `` The Unapologetic Fat Girl 's Guide to Exercise and Other Incendiary Acts . '' `` Orgasm is not a pants size . Fun is not a body fat percentage , '' Blank said . `` There is not a magical BMI number that produces love . End of story . '' Do you think obesity can present special sexual challenges ? Share your experience in the comments section below .
`` XL Love '' book outlines how obesity is changing the love lives of Americans . Author Sarah Varney does n't see it as a fat-shaming or fat-advocacy book . Body image activist : `` There is not a magical BMI number that produces love . End of story ''