American credit card users love their rewards.

And why shouldn’t they? If you’re a responsible card user, you can essentially get perks — in the form of points, miles or cash back — for spending money you were going to spend anyway.

But if you’re going into debt to pursue rewards, you’re making a major misstep, credit experts say.

It’s a more common error than you may think. Of the 48% of U.S. cardholders who carry a balance from month to month, 67% say they try to maximize their rewards, according to a recent survey from Bankrate. Run the numbers, and it’s easy to see how this is a problem for consumers, says Ted Rossman, senior industry analyst at Bankrate.

“It’s a big mistake because the average credit card interest rate is more than 20%,” he says. “Even a good rewards card is paying maybe 3%, 4%, 5% or 6% back.”

Credit experts agree: Rewards programs are only worth it if you can pay your cards off in full every month.

But running a tab while you chase rewards isn’t the only blunder they see among cardholders. Here are two more common mistakes they say may be costing you money.

If you have a cash-back strategy and pay your card off every month, you don’t have much to worry about. Just check in every so often and redeem your cash as you see fit — either as a statement credit, a direct deposit into your account or as online payment for goods and services.

You may have a similarly lax attitude about letting your rewards accumulate if you have miles or points. After all, if you wait long enough, you may build up a big enough cache to finally take that luxury flight.

But it’s important to remember that points and miles aren’t counted the same as straightforward cash back. “Valuations are always in flux,” says Daisy Hernandez, credit cards editor at The Points Guy.

Hernandez recently planned to travel using points from a co-branded hotel card.

“They do dynamic pricing, meaning that depending on location or whether it’s peak season it could be more expensive, whether it’s cash or points,” she says.

At the time she originally planned her trip, her hotel rewards points were worth roughly 0.8 cents a piece she says. Her plans fell through, and just a few months later, they were worth closer to 0.6 cents, she says.

That’s not to say you shouldn’t ever save up any rewards. But, “you don’t want to hoard points and miles,” says Rossman. “You don’t want to be a points millionaire. It’s not like a 401(k).”

Hernandez’s colleagues at The Points Guy put it even more succinctly: “The general guidance is, earn and burn.”

It’s hard to see tales on social media where people game the credit cards reward system to book once-in-a-lifetime trips and not feel like you want in.

But if you want to get into the rewards game, you have to be excited to actually play it, says Matt Schulz, chief credit analyst at LendingTree and author of “Ask Questions, Save Money, Make More: How To Take Control Of Your Financial Life.”

“One of the biggest fundamental mistakes that people can make people is, they see influencers talking about flying first class to Paris or Bangkok, and they don’t necessarily understand the work that goes into it,” he says.

To get the best deals, you have to be able to pull the trigger on offers to boost the value of your rewards, often by transferring them to a partner of your card issuer, says Hernandez. “If you’re looking to get the most value out of your rewards, you’re checking daily,” she says.

If you’re not nimble about snagging great deals, you may find yourself using your points in suboptimal ways, says Rossman.

“They may try to get you to exchange your [travel] points for merchandise like luggage or kitchen tools, and you’re usually better off just getting cash back,” he says. And if you were going to get cash back anyway, you might have been better off skipping a points or miles card altogether, he adds.

Plus, if you’re opening a slew of cards to try to maximize your rewards, you up the chances that you’ll mismanage your credit and miss payments, says Schulz.

“It’s a really big deal,” he says. “It can hurt your credit and do damage that far outweighs any credit card rewards you would get.”

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While the brain makes up only 2% of your body weight, it is responsible for over 20% of energy expenditure each day.

I’ve spent 15 years studying the brain, and five years as a medical director of a residential memory care facility. I am always reminding people to eat things that feed the brain, not harm it. You want to give your brain the nutrients it needs to heal, repair tissues, fight toxins and create neurotransmitters so that it can stay young, sharp and energized for as long as possible.

That means nutrient-dense, lower-carb foods. Nutrients to provide the building blocks, and lower carbs to help stabilize your blood sugar and even out the roller coaster of spikes and drops that create so many cognition-impairing side effects, including lightheadedness, anxiety, fatigue, irritability and a decrease in focus.

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So if you do one thing to improve your diet to protect the brain, start raising your carb-consciousness and begin swapping out some of the carb-heavy foods you eat most often for lower-carb alternatives.

A healthy amount of carbs to shoot for is around 130 grams per day (about 25% of calories in a 2,000 calorie diet).

But not all carbs offer the same health benefits, so the quality of the carbs you eat is much more important than the number. Consider that eating a higher carb fruit like grapes or watermelon after a high-fat, high-protein snack like greek yogurt will reduce how quickly and how much your blood sugar will go up.

Eat high-fat, high-protein foods first in your meal and save the higher carb options until later. Aim to snack on low-carb options like cucumbers, bell peppers, cheese, coconut yogurt, pecans or walnuts.

Sweets on an empty stomach will raise your blood sugar high and fast, then it will drop. Generally that drop in blood sugar feels bad and makes us act hangry, and over time it leads to diabetes, insulin resistance and cognitive impairment. 

That could look like:

• One piece of avocado toast for breakfast instead of a whole bagel or cereal.
• Soup and salad instead of a sandwich and chips for lunch.
• Swapping your side dish of potatoes or rice for quinoa or cauliflower rice at dinner.
• Berries with a little whipped cream or a few squares of dark chocolate instead of ice cream for dessert.

Don’t get too hung up on counting every gram of carbohydrates you consume, because it can be stressful and overwhelming (which is the opposite of what we want!).

But many times my patients don’t realize how many carbs they’ve been eating. Becoming aware of how many carbohydrates you’re eating in a day will help you eat less of them — after all, you can’t change a habit you don’t know you have.

Just this one change would do a ton of good — including bringing down glucose and insulin levels (and therefore reducing inflammation), and upping consumption of the nutrients that support brain health (protein, vitamins and minerals from vegetables and fats).

Dr. Heather Sandison is a naturopathic doctor specializing in neurocognitive medicine and the founder of Solcere Health Clinic, a brain optimization clinic, and Marama, the first residential memory care facility to have the goal of returning cognitively declined residents to independent living. Her latest book, “Reversing Alzheimer’s” is out now.

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Adapted excerpt from the book: “REVERSING ALZHEIMER’S,” by Dr. Heather Sandison. Copyright © 2024 by Dr. Heather Sandison. Reprinted courtesy of Harper Books, an imprint of HarperCollins Publishers.

People love to talk about themselves. On dates, in the office and especially on social media, you’ll often hear others trying to make themselves seem impressive.

It rarely works, says Adam Grant, a bestselling author and organizational psychologist at the Wharton School of the University of Pennsylvania.

“For the most part, bragging about your accomplishments is ineffective and often counterproductive, because people don’t consider you a credible source of what you’re a genius at,” says Grant, who’s studied human behavior for over 20 years, including “lots of research on self-promotion.” 

Talking yourself up can even backfire: “Constantly broadcasting successes is not a sign of success,” Grant wrote on LinkedIn last month. “It’s a mark of insecurity. Insecure people only talk up their wins. They brag to get attention.”

The real way to not look like a brag-a-lot is to get others to do the talking for you, says Grant: “You really want other people to sing your praises, because they’re more credible, and that doesn’t call your character into question.”

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You can do that by cultivating strong relationships with the people around you, both personally and professionally. In the workplace, for example, you might help your manager train new hires, or regularly contribute creative ideas in your team meetings. When you’re up for a promotion, your boss can then easily recommend you as someone who’s a helpful, creative team player.

Lisa Skeete Tatum, CEO of the career coaching platform Landit, calls these kinds of people “sponsors.” They can speak to your strengths and abilities when you’re not there, she told CNBC Make It in 2022.

“I would not be where I am today if it wasn’t for people who believed in me … who saw something in me and took a chance, who helped me see things I didn’t even know were possible,” said Tatum.

If you’re in a situation that demands self-promotion, like a job interview or a performance review, Grant recommends speaking about any accolades and accomplishments that you can verifiably prove.

Instead of saying you’re the most athletic person in your family, for example, say you’ve completed the New York City Marathon twice. “Make sure you’re sharing things that are objectively verifiable, as opposed to bragging about how you’re a genius or the best public speaker in world history,” says Grant.

Then, mention the challenges you faced along the way, like finding the right space or building your endurance. “Secure people are open about their failures too,” he wrote on LinkedIn. “They share their peaks and valleys to inspire others.”

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Steve Barsh spends his workweeks mentoring startup founders, consulting with artificial intelligence experts and advising organizations like SeatGeek and NASA.

For one to two hours per day, the full-time startup investor also runs his side hustle, a property management company called Parker Chase Properties that manages short-term rentals across five luxury condo units in Park City, Utah, and Deer Valley, Utah.

The side hustle started 26 years ago when Barsh sold a software startup he co-founded called SECA, and together with his wife Amber Salzman, bought a $820,000 three-bedroom condo in Park City. The Philadelphia-based couple used the condo for vacations and rented it out through a property manager for the rest of each year — until Barsh, annoyed at how much he had to pay the property manager, decided to handle bookings himself, he says.

Salzman and Barsh now own four of the five condos managed by Parker Chase, which brought in $1.27 million in revenue — roughly $105,000 per month, on average — on Airbnb, VRBO and travel software platform Hospitable last year, according to documents reviewed by CNBC Make It. (Barsh is an investor in Hospitable, according to the company.)

Barsh pockets 40% to 50% of those bookings as profit, he estimates. He essentially runs the side hustle solo, contracting only with a housekeeping company and, when he’s traveling, a backup property management company, he says.

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Now a full-time Park City resident, Barsh “refined” his guests’ experience over time, he says. He pictured travelers wanting to kick back in leather chairs, drink cold beers from a mini fridge and watch ESPN on a wall-to-wall flat-screen TV — when they weren’t skiing on nearby slopes — and spent to make such luxuries possible, anticipating that the investment would pay off later.

He collects feedback from guests constantly, and refuses to cut corners, he adds. Most of the time, Parker Chase’s positive reviews come from small details, like lint rollers in the laundry room. Once, one of Parker Chase’s regulars told Barsh that she desperately needed a rice cooker, he says. He stopped at Costco and texted her a photo of one on the shelf.

“She was like, ‘Not a crappy American rice maker, a Chinese rice maker,’ and sent me a link to a $390 version,” Barsh says. “It was a no-brainer for me.”

Barsh’s property management side hustle is decidedly upscale — it’s hard to create a luxury experience for guests without spending money first, including the roughly $10 million he and Salzman spent to purchase their four condos, he says. (The funds came from a $4.3 million sale of their initial condo, and money that Salzman, a longtime biotechnology executive, made in a corporate acquisition, Barsh notes.)

Correspondingly, a night at a Parker Chase property is pricier than the average vacation rental: The company’s current availability for March shows a median price of $3,390 per night. The average daily rate for an Airbnb or VRBO listing in Park City is $761, according to an estimate by short-term rental analytics company AirDNA.com.

Barsh pockets more money from Parker Chase than the combined salaries of the average property manager and real estate investor in the U.S., based on data from job search platform ZipRecruiter. He also uses his side hustle to teach his two children how to invest in appreciating assets, and he genuinely enjoys the hospitality aspect of running the business himself, he says.

“Four Seasons, when they hire people, know that they can teach people how to work a front desk, open a front door or clean a room, but they look for people with that hospitality instinct,” says Barsh. “I don’t know what it is in me, but I really enjoy hospitality. I really enjoy when people tell me they’ve had an amazing experience. It just makes me feel good.”

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Talking about money can be awkward or embarrassing if you’re not used to it. But having financial conversations with friends, coworkers and even the person you just started dating can help you learn if you’re being paid fairly, how “normal” your financial habits are or how to start investing outside of your 401(k). 

One of the most important people you should be having routine financial conversations with is your romantic partner or spouse. If you’re not aligned on financial goals and strategies — from when to move in together to where to go on vacation — there’s a good chance money will be a point of contention in your relationship. 

“Once you and your partner know how to talk about money, everything changes,” self-made millionaire Ramit Sethi writes in his new book, “Money for Couples.” “You’ll both know why you’re saving, investing and even spending.”

After more than 20 years speaking with thousands of couples, Sethi has identified a few phrases you can use to have healthier financial conversations and, in turn, a better relationship with money. Use these two phrases to start having better financial conversations with your partner. 

When you are in a serious relationship or marriage, you should be asking your partner what your rich life looks like together.

“This is a conversation that you should be having regularly. What is our rich life? What’s important to us?” Sethi tells CNBC Make It.

A rich life, in Sethi’s eyes, is one where you and your partner don’t argue about money and aren’t too worried about how the bills are getting paid each month because you have a comprehensive understanding of your numbers, including your household income and all of your fixed costs. 

You know generally how much you’re able to spend “guilt-free” each month and what you’re interested in spending it on as a couple. If you decide traveling together is a priority, you may agree to skip dining out so you can put that money toward trips instead. 

A rich life isn’t about the amount of money you’re spending on things, but rather “an expression of your ideal life in which your money, relationships and leisure time work beautifully,” Sethi writes. 

Similar to your rich life conversations, Sethi encourages couples to establish a culture within their homes to help guide how you spend your money together. He offers the open-ended phrase “In our family, we…” to set you up to determine what your family’s standards are. You may say “In our family, we cook together,” or “In our family, we take road trips versus flying,” for example.

If you say, “In our family, we never get into credit card debt,” follow that up by putting systems in place to avoid carrying a balance month to month or using credit cards altogether. You may ultimately avoid arguing about a big credit card bill in the future.

“In our family, the first Sunday of each month, we always sit down with a coffee and we talk about money, starting with a compliment,” Sethi adds as an idea. “That is how you create a healthy money culture in your household.”

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