Trina Kennington knows she could be a better mother if only it wasn't so hot outside.
Diagnosed with reverse seasonal affective disorder two years ago, the mother of five struggles with a type of depression that sets in as the days grow longer and the temperature rises. Hers is a lonely affliction, coming at a time when it seems that everyone else is happy to be on vacation or outside enjoying the sunshine and warmth.
"On social media, everyone is doing fun things, and I am not. Not because of lack of money or time, but because of my mental state," said Kennington, who lives in Riverton.
"I could have been a better mom. I'm just this crazy sun-hating mom. I become a fun mom in the fall, but summer is when we have our kids around so it's hard."
Summer depression, or reverse SAD, affects about 1 in 10 of the estimated 14 million people who suffer from seasonal depression, according to Barbara Danner, a mental-health counselor at Aspen Ridge Counseling Center in West Jordan.
First added to the Diagnostic and Statistical Manual of Mental Disorders in 1987, seasonal affective disorder is considered a serious form of depression when it occurs for at least two consecutive years, begins at a set time each year and abates with the change of season.
Some researchers have challenged the condition's existence, saying there isn't sufficient evidence that depression can be predicted by Earth's movement around the sun. And while winter blues are widely thought to be a consequence of reduced exposure to light, even the psychiatrist who first described the disorder says he can't fully explain why the onset of summer could cause people, most often women, to be depressed when light is plentiful.
But for sufferers like Kennington, the condition is real, and most mental health professionals treat it as such.
"If somebody has depression, it's depression. We identify that, and we take care of it," said Dr. Jason Hunziker, a psychiatrist who teaches at the University of Utah.
Dr. Norman Rosenthal is widely credited as the first physician to use the phrase "seasonal affective disorder" to describe patients he and colleagues studied in Maryland whose depression seemed cyclical. Rosenthal, who later wrote a book called "Winter Blues," believes that winter depression is primarily caused by reduced exposure to light and he pioneered the use of artificial light as a treatment.
Sunlight helps control our sleep-wake cycles by stimulating the production of melatonin, the hormone that helps make us sleepy. One study at Brigham Young University found a connection between mood and the number of hours of light in a day, regardless of whether people suffered from seasonal depression.
But Rosenthal and others believe there's more than light exposure involved. Some researchers believe that people who suffer from winter depression may also have abnormalities in the genes that govern serotonin transmission, or that their eyes might not process light normally. Others suggest the condition might be heritable or made worse by stress.
Regardless of the cause, the treatment for winter depression, in addition to antidepressants, often includes more light, either naturally or with special lamps made for "light therapy."
That's not an option for most people who are depressed during the summer and, like Kennington, can't bear the sun and heat.
Greg Flick, a teacher in Syracuse, New York, said he experiences the onset of depression as early as April and finds his symptoms get worse as the temperatures rise.
"There is a range of temperatures people feel comfortable in. My set points, my high temperatures, are close to (everybody else's) lows," he said.
Kennington, the mother of five in Utah, said she knows the sun has benefits, including being a source of Vitamin D, and so she said she gets "every minute outside" in the spring. "The sun is your friend, but I personally can't do it in the mid-summer," she said.
Michelle Franklin, a Canadian who wrote a book called "I Hate Summer," was diagnosed with the disorder four years ago, and said she also has fibromyalgia, which for her, gets worse when it's hot. In an email exchange, Franklin said she is looking forward to the sun dying out, and she's only partly kidding.
"Like any depression, it will make you believe there will never be relief, there will never be another day of fine weather, there will never be happiness again. The old adage of there never being sunshine hilariously does not apply here," she added.
But although the cause of summer depression remains unclear, Franklin said she is sure hers is not caused by lack of sunlight since she avoids it. "I used to wonder (about) this, but my symptoms always worsen after being out," she said.
Even Rosenthal says no one has been able to pinpoint a cause, and there have been few studies specifically on summer depression.
"Is it the heat, is it the light, is it both, or is it the biological rhythms? These are all viable theories of what's going on, but we don't know it is," Rosenthal said. "But as the world gets hotter, summer depression is going to become more and more important because heat does seem to be a factor for many people."
With little research to provide evidence for a cause or a cure, summer depression has its skeptics, among them Steven LoBello, a professor of psychology at Auburn University in Montgomery, Alabama, and co-author of a 2016 study that concluded seasonal variations in depression are "strongly rooted in folk psychology" and are not supported by objective data.
LoBello and his co-authors surveyed data collected through the Behavioral Risk Factor Surveillance System, an annual survey of the Centers for Disease Control and Prevention. They analyzed the responses of 34,000 who were asked, among other things, about depressive symptoms, and found no evidence for cyclical changes based on the altitudes where people lived, or for the time of year.
"Merely being depressed duringwinter is not evidence that one is depressed becauseof winter," the authors wrote, arguing that mental-health practitioners should consider dropping seasonal variations as a factor in diagnosing depression.
LoBello, who has done further research on the topic that has not yet been published, said he and his co-investigators didn't set out to challenge the existence of seasonal affective disorder, but simply to look at its incidence, and they were surprised that they found no seasonal variation in depressed individuals in the survey. "Across time, (depression) was very flat, very stable," he said.
LoBello also said that studies on the disorder that he has seen don't control for other possible causes; for example, people could be depressed in winter because they're not as physically active in winter, not because they're deprived of light.
"You haven't just taken away darkness or light (when the season changes); you've taken away a whole lot of other things," he said.
And, in fact, two of the symptoms of summer depression — insomnia and loss of appetite — could be explained by factors other than sunlight. Studies have shown that people sleep better in cooler temperatures, regardless of season, and among many species, appetite decreases when it's hot, since eating generates heat.
But there's one thing that skeptics of summer depression can't refute: Suicide is highest in late spring and summer, researchers say.
Hunziker, at the University of Utah, said most researchers believe being exposed to too much light is at the root of summer depression, but he acknowledges that there are a variety of factors at play.
"If you have kids, they're gone all year, and all of a sudden, they're home and you have to make arrangements. Schedules get hectic in the summer, there are vacations that cost money, finances get tight. There are a lot of factors that go into depression in the summertime," he said.
"I don't know about you, but if I get in a hot, muggy environment, I get pretty agitated, and if I lived in that environment all the time, I'd spend most of my time agitated. And if you don't sleep because you're hot, then that sets you up for depression."
Mental-health professionals believe it's this agitation that is responsible for the spike in suicides that occurs when temperatures rise.
"In winter, in winter depression, our bodies slow down. It's almost like we're hibernating. We're slowing down; we're eating more," Hunziker said.
"In summer, we're more awake and alert and restless, and that leads to people attempting suicide. It's when you have that extra energy and you feel terrible, you feel depressed that you actually have the energy to act on those thoughts."
Hunziker and other mental-health experts say it's important for people who have seasonal depression to get help in advance of the season in which they suffer.
"If we know in June someone starts getting depressed, we want to start them on an antidepressant toward the end of April so it's fully therapeutic by the time June rolls around," Hunziker said. "And some people, who have it every year just stay on the medicine."
Beyond medicine, there are other simple things that people can do to combat summer depression. Be sure that your living environment is cool, and your bedroom is dark, so your sleep disruptions are minimal. Plan ahead for vacation costs and summer camps and daycare.
"Eating well, exercising, even for us older folks, it's still helpful to keep us stable. It's got to be more than just medicine, and of course, therapy can also be utilized to help people manage and help people cope," Hunziker said.
Danner, the licensed mental health counselor in West Jordan, said she helps patients "reframe" the way they think about summer and identify positive activities they can do. She encourages people to take a Vitamin D supplement, especially if they're shunning the sun.
Danner herself prefers winter to summer, and says, "I love it to be cloudy and rainy every day."
"I am in a happy, productive mood in winter. The moment the sun comes out, I am like a vampire," she said. "I recently remodeled my house, and I was like, 'Keep it dark.'"
She recommends that people who suffer from summer depression keep their homes cool, incorporate swimming, take lots of showers, and "make a conscious effort to keep those supplements going and get healthy light."
Rosenthal, the psychiatrist who first identified seasonal affective disorder, said it's easier to treat depression before it is established, but for people experiencing depression, it's not too late to get on an antidepressant even in July. "We still have a couple of hot months ahead of us, and (medication is) easy to take, as opposed to going swimming in a cold lake."