How to look and feel healthier in one month, according to science

Most Americans are consuming 50% more than their daily recommended salt intake, according to the Centers for Disease Control and Prevention. Over time, this can take a toll. When there's too much salt in your blood, your kidneys have a hard time flushing out impurities, which can raise your blood pressure.

Instead of salty snacks, try incorporating more whole foods like bananas and avocados into your diet this month, since those are loaded with potassium, a natural antidote to sodium's harmful effects on your blood pressure.

There are plenty of other flavor-boosters to include in your meals instead of salt, like lemon juice and herbs. Whatever strategy you choose, avoid processed foods, which not only have lots of hidden salt, but may also be linked to higher cancer rates.

Fiberous foods help keep your energy levels more stable than quick-burning sugary or carb-heavy fixes. Fiber also keeps your tummy full and your digestive system humming along smoothly.

There's a lot of fiber in whole grains, fruits, nuts, and vegetables. A lot of the best high-fiber foods also have a low glycemic index, which could spare you from suffering sugar crashes.

A lack of sleep can make people more accident-prone, up your odds of getting sick, and put extra stress on your heart. Increasingly, bad sleep is also being linked with cancer. The World Health Organization warns that messing with your sleep schedule by working the night shift is probably carcinogenic. Sleepiness is also now being blamed for cases of colon, breast, and prostate cancer.

Just a week without enough sleep — defined as four hours a night for six nights in a row — can cause blood-sugar levels to spike enough that doctors could diagnose you with pre-diabetes. That's because your tired body's cells become less receptive to insulin, according to sleep expert Matthew Walker, the author of "Why We Sleep."

As Walker says in his book, "when your sleep becomes short, you will gain weight."

Walker recently revealed his own formula for good sleep to Business Insider. He gives himself a nightly eight-hour window of "sleep opportunity," meaning that he's powered down and his head is on the pillow during that time, even if he's not catching eight full hours of shut-eye.

Given that an adult's body weight is up to 60% water, it's no surprise that staying hydrated is associated with a host of health benefits. Getting enough fluid ensures your body can efficiently flush out impurities, stay energized, sweat, and more easily pump blood around.

It's also a weight-loss strategy.

A 2016 study of more than 18,000 people in the US found that those who drank more water were consistently more satisfied and ate fewer calories on a daily basis. Those people also consumed lower amounts of sugar, fat, salt, and cholesterol than more dehydrated participants.

Another relatively small study in 2015 found that people who stayed well-hydrated by drinking water 30 minutes before eating their meals could lose upwards of 5 pounds in three months.

Drinking coffee can also improve your heart health and reduce your risk of developing Type 2 diabetes and certain kinds of cancer — if you drink it in moderation. The idea that a couple cups of coffee might dehydrate you has been debunked.

The best way to care for your skin in the summer is to protect it from the sun's harsh rays. Many dermatologists suggest starting your day with a moisturizer that includes sunscreen, which will both keep skin looking young and help prevent skin cancer.

SPF 30 is enough for most people, but if you're going to be in the sun, remember to reapply every two hours or so (since sunscreen only offers its full protection for that long).

If it's dry skin you're worried about, David Leffell, chief of dermatologic surgery at Yale School of Medicine, recommends a moisturizer with lactic acid as a main ingredient. Lactic acid is also used by dermatologists when they perform chemical peels.

Be wary of products like wipes and makeup removers that list "alcohol" or "isopropyl alcohol" as primary ingredients, because those will further dry out your skin.

It can take a month or more for fresh skin cells to turn over on the surface of your body, so you won't be able to gauge the results for at least a few weeks after starting a new skin routine.

While some people believe that consuming certain foods will help your complexion, that's generally not an evidence-backed strategy.

"Whether it's avocados or salmon or omegas, they get digested and they don't selectively go to your skin," Leffell recently told Business Insider.

If you're looking to take the edge off, exercise can trigger an immediate endorphin-fueled high and also improve your mood longer-term.

In a small study of 39 women, participants took part in 50-minute aerobics training sessions twice per week for three months. Researchers found that their moods improved "significantly" by the end: the women were more optimistic, less anxious, and had a greater sense of self-efficacy.

Conversely, researchers tracked more than 7,000 people over two decades in the Wisconsin Longitudinal Study, and found that older adults tended to get crabbier if they became less physically active as they aged. In other words, being a couch potato can make you less agreeable, less enthusiastic, and more negative.

Scientific research on meditation is still evolving, but if you're looking to reduce anxiety, keep your blood pressure in check, or lower your stress levels, you might want to give it a go.

The National Institutes of Health says "meditation may reduce blood pressure, symptoms of irritable bowel syndrome, anxiety and depression, and insomnia," based on what we know so far.

More research is needed, but if you're curious, journalist Dan Harris' 10% Happier website offers some simple tips on how to get started with your own meditation practice.

Feeling drowsy around 2 p.m. is normal and natural, since that's one of two daily lows in our circadian rhythm. During that time, people tend to feel sleepier and colder. (You might not notice the other lull, because it happens around 3 a.m.).

If you're looking to make the most of your afternoons, you can try gulping a cup of coffee then taking a 20-minute snooze. That's short enough that you won't wake up groggy, and just the right amount of time for the fresh caffeine to kick in and get you going.

Short naps have been shown effective at helping air traffic controllers working the night shift stay alert. One small study of 10 Japanese students found that 20-minute coffee naps quickened the students' reaction times on computer tasks for an hour after they woke up.

Remember that it's alright to not feel great all the time.

A 2017 set of studies of more than 1,000 people found that those who were more accepting of their negative emotions and thoughts (and less judgmental about them) were less likely to suffer depressive or anxious symptoms months later.

The researchers said that accepting your emotional states can help keep you from "reacting to—and thus exacerbating" negative mental experiences.

Imagining being and doing their best can help students perform better and feel better.

A 1998 study of nearly 300 high school students revealed that teens who "imagined themselves achieving as a result of hard work" did better academically and were more persistent.

Another study of more than 60 undergraduates found that a month spent regularly contemplating what your "best possible" future self might look like boosted students' moods significantly and immediately.

Here's how to try it, according to those researchers:

"Imagine yourself in the future, after everything has gone as well as it possibly could. You have worked hard and succeeded at accomplishing all of your life goals. Think of this as the realization of your life dreams, and of your own best potentials... you are identifying the best possible way that things might turn out in your life, in order to help guide your decisions now. You may not have thought about yourself in this way before, but research suggests that doing so can have a strong positive effect on your mood and life satisfaction."

Nurturing your most intimate partnerships with others is crucial.

The best evidence for this to date comes from an 80-year study of more than 250 men who were sophomores at Harvard during the Great Depression. (The study later expanded to include their offspring, too.) The results suggested that close, nurturing relationships were more important to long-lasting happiness than wealth, intelligence, or even genetics.

"Good relationships don’t just protect our bodies; they protect our brains," study director Robert Waldinger said in a TED talk. "And those good relationships, they don’t have to be smooth all the time. Some of our octogenarian couples could bicker with each other day in and day out, but as long as they felt that they could really count on the other when the going got tough, those arguments didn’t take a toll on their memories."

Similarly, a German study published in May found that people who spent a year making a renewed effort to help others or spend more time with friends and family measurably increased their own rating of satisfaction with life.

The idea that it takes three weeks to form a new habit is a myth — research suggests it can actually take anywhere from a couple weeks to more than 250 days.

As habit expert Wendy Wood said at the 2014 American Psychological Association conference, "it's easier to maintain the behavior if it's repeated in a specific context."

So pick a consistent time of day (like first thing in the morning) or a certain place (as in, the gym or a nearby park) to help you cement your new activities into routines.

Yale psychologist John Bargh previously told Business Insider that whatever you do, it's important to stick to your self-imposed schedule.

"You don't wanna make promises that you don't keep to your body and your mind," he said. "It's a relationship like any other, and you have to establish trust."