Age plays a major part in people who are infected with cold, i. e, in people who suffer from cold infection. A study done by University of Michigan has shown information that seems to be true for the general population. Babies are the most cold infected group, generally more than six colds in their first year. Boys have more colds than girls up to the age of three. After three, girls are easier to get infected with cold than boys, and teenage girls get three colds a year to boys' two. The general cold infections continue to get less into adults. Elderly people who are in good health have as few as one or two colds every year. One interesting thing is found among people in their twenties, especially women, who show a rise in cold infection , because people in this age group are most likely to have young children.

The study has also found that economy plays an important role as well. With more and more income, the frequency at which colds are reported in the family is getting lower and lower. Families with the lowest income usually live in rooms more crowded than rooms owned by richer people, and the crowding usually leads to more chances for the cold virus to travel from person to person. Low income may also have an effect on our diet. Many scientists believe that a poorer diet usually leads into more possibilities of cold infection.

Mom noticed that something was wrong when I started getting so thirsty. I’d have a lot to drink before bed, which was unusual for me. One time, I opened a big container of apple juice and kept refilling my glass. Before I knew it, I’d drunk the entire container! My mom called my doctor. I then had a few blood tests, and the results were certain — I had diabetes (糖尿病), which meant that the amount of sugar in my blood was very high. That can be dangerous, so I had to learn how to control my blood-sugar level.

My eating habits had to change in a big way. With diabetes, I can’t eat a lot of sugar or carbohydrates (碳水化合物). I have to figure out exactly how much sugar I plan to eat, and then I get an injection of insulin (注射胰岛素) before the meal to help my body process the food. Also, I test my blood-sugar level often. I’m always trying to keep my blood sugar at a healthy level. The level can drop when I exercise, but that doesn’t keep me out of gym class or off the basketball court — I just keep some juice boxes around to boost my blood sugar if I need to.

It’s a lot of work and not a lot of fun to keep track of everything, but I’ve gotten used to my new habits. I was a little scared at first because I wasn’t sure how my life would change. Once I knew what I needed to do, though, it wasn’t a big deal. My life is different now from what it was before, but it has become completely regular to me.

Your grandpa probably complained that rain was coming---he could feel it in his knees. We wouldn’t want to question an elder’s wisdom, but is there any scientific basis in his claims? One expert, Elaine Husni, director of Cleveland Clinic’s Arthritis(关节炎) and Musculoskeletal Center, explains the effects of barometric pressure (气压) and why these aches and pains could be telling.

Dr. Husni says that many, but not all, of her osteoarthritis patients complain that weather does influence their pain levels. “There is some consensus that lower barometric pressure and dropping temperatures correlate with more joint pain,” says the Cleverland doctor. Barometric pressure---essentially the weight of the air around us---drops when it gets colder. The thinking, she explains, is that lightness can cause the thin lining known as the joint capsule(关节囊)， which surrounds joints and maintains lubrication(润滑), to expand and stretch nerves, causing pain. A similar phenomenon can occur with humidity changes: There can be shifts in pressure that cause swelling around the joints, Dr. Husni says.

Theories include that “patients with arthritis already have inflammation(炎症) of their joints(specifically around the joint capsule) so any additional changes in the atmosphere could be detected more easily,” she says. “Perhaps the nerve endings are more sensitive in patients with arthritis.”

People with migraines (偏头痛) sometimes insist they feel headaches coming on when the air turns cold and the air pressure drops. These are called barometric pressure headaches, and a small study of 31 migraine sufferers in Naples, Italy, found that low pressure can lead to constricted(收缩的) blood vessels and result in more severe headaches, though the reasons, according to scientists, aren’t totally clear.

Dr. Husni is quick to point out that clinical studies have been conducted to find direct correlations between patients with hip or knee pains and changes in the weather, but the results were mixed. “There does seem to be a loose association between certain temperature variables like barometric pressure, cold temperatures and humidity and increased joint pain, but it isn’t so easy for patients to say with precision, ‘It will be 60 degrees and rainy tomorrow,’” she says. While many patients do feel more pain when it gets cold or humid, “they are not psychic(灵媒). In studies, they couldn’t predict the weather with accuracy.”

The studies Dr. Husni cites don’t pinpoint (准确描述) an exact time of when pain is set off by changing temperatures, nor has she seen evidence that certain climates are better for those with joint pain. “A lot of people with osteoarthritis say they do better in warmer climates, but the changes in climate aren’t always clinically meaningful,” says the joint expert. She cites a study that tracked online searches for terms related to arthritis and knee and hip pain and weather changes across 5 years in 50 American cities. When temperatures fell to between minus 5℃ and 30℃, search volumes(量) for hip pain increased by 12 index points, and knee pain increased by 18 index points; above 30℃, search volumes dropped by 7 index points. Still, says Dr. Husni, the study didn’t prove predictive abilities---just curiosity. “It’s not like you need to move to a warmer climate,” she says.

Blustery(大风的) weather may indeed increase pain in those who suffer from joint pain, but Dr.Husni suggests some basic fixes. No matter your local climate, keep your core warm and dry, she says. A sweater, scarf and gloves are perfectly fine well into March. No hard evidence suggests that applying heat or cold will eradicate joint pain. But “if an ice pack feels good or a heat pad helps, I’m not going to stop my patients from using them,” she says.

Anti-inflammatory medications are also go-tos, but Dr. Husni encourages patients with arthritis and other joint discomfort to seek medical advice. “Consult your doctor, who can treat you personally, she says. “Osteoarthritis affects 27% of Americans, and there are a lot of experts out there. Get diagnosed, get help, and you don’t have to suffer in bad weather.