Month: July 2022

Be honest: just how much television are you watching? One study has estimated that half of American adults spend two to three hours each day watching television, with some watching as much as eight hours per day.

Is time spent on TV a good thing or a bad thing? Let's look at some of the data in relation to your risks for cognitive decline and dementia.

Physical activity does more to sharpen the mind than sitting

First, the more time you sit and watch television, the less time you have available for physical activity. Getting sufficient physical activity decreases your risk of cognitive impairment and dementia. Not surprisingly, if you spend a lot of time sitting and doing other sedentary behaviors, your risk of cognitive impairment and dementia will be higher than someone who spends less time sitting.

Is television actually bad for your brain?

Okay, so it's better to exercise than to sit in front of the television. You knew that already, right?

But if you're getting regular exercise, is watching television still bad for you? The first study suggesting that, yes, television is still bad for your brain was published in 2005. After controlling for year of birth, gender, income, and education, the researchers found that each additional hour of television viewing in middle age increased risk for developing Alzheimer's disease 1.3 times. Moreover, participating in intellectually stimulating activities and social activities reduced the risk of developing Alzheimer's.

Although this study had fewer than 500 participants, its findings had never been refuted. But would these results hold up when a larger sample was examined?

Television viewing and cognitive decline

In 2018, the UK Biobank study began to follow approximately 500,000 individuals in the United Kingdom who were 37 to 73 years old when first recruited between 2006 and 2010. The demographic information reported was somewhat sparse: 88% of the sample was described as white and 11% as other; 54% were women.

The researchers examined baseline participant performance on several different cognitive tests, including those measuring

• prospective memory (remembering to do an errand on your way home)
• visual-spatial memory (remembering a route that you took)
• fluid intelligence (important for problem solving)
• short-term numeric memory (keeping track of numbers in your head).

Five years later, many participants repeated certain tests. Depending on the test, the number of participants evaluated ranged from 12,091 to 114,373. The results of this study were clear. First, at baseline, more television viewing time was linked with worse cognitive function across all cognitive tests.

More importantly, television viewing time was also linked with a decline in cognitive function five years later for all cognitive tests. Although this type of study cannot prove that television viewing caused the cognitive decline, it suggests that it does.

Further, the type of sedentary activity chosen mattered. Both driving and television were linked to worse cognitive function. But computer use was actually associated with better cognitive function at baseline, and a lower likelihood of cognitive decline over the five-year study.

Television viewing and dementia

In 2022, researchers analyzed this same UK Biobank sample with another question in mind: Would time spent watching television versus using a computer result in different risks of developing dementia over time?

Their analyses included 146,651 people from the UK Biobank, ages 60 and older. At the start of the study, none had been diagnosed with dementia.

Over 12 years, on average, 3,507 participants (2.4%) were diagnosed with dementia. Importantly, after controlling for participant physical activity:

• time spent watching television increased the risk of dementia
• time spent using the computer decreased the risk of dementia.

These changes in risk were not small. Those who watched the most television daily — more than four hours — were 24% more likely to develop dementia. Those who used computers interactively (not passively streaming) more than one hour daily as a leisure activity were 15% less likely to develop dementia.

Studies like these can only note links between behaviors and outcomes. It's always possible that the causation works the other way around. In other words, it's possible that people who were beginning to develop dementia started to watch television more and use the computer less. The only way to know for sure would be to randomly assign people to watch specific numbers of hours of television each day while keeping the amount of exercise everyone did the same. That study is unlikely to happen.

The bottom line

If you watch more than one hour of TV daily, my recommendation is to turn it off and do activities that we know are good for your brain. Try physical exercise, using the computer, doing crossword puzzles, dancing and listening to music, and participating in social and other cognitively stimulating activities.

About the Author

Andrew E. Budson, MD, Contributor; Editorial Advisory Board Member, Harvard Health Publishing

Dr. Andrew E. Budson is chief of cognitive & behavioral neurology at the Veterans Affairs Boston Healthcare System, lecturer in neurology at Harvard Medical School, and chair of the Science of Learning Innovation Group at the … See Full Bio View all posts by Andrew E. Budson, MD

Three months into the year is a good time to recalculate if you’ve been slacking on your resolution to eat healthy. And if you’ll be leaving home base or school soon and foraging for yourself (plus or minus roommates), it’s a great time to learn about healthy, low-cost choices for your grocery list.

The basics: A weekly shop

A healthy diet is rich in vegetables, fruits, legumes (beans or lentils), whole grains, nuts, seeds, lean proteins, and low-fat dairy products. Trying to fill your cart with all of those goodies can feel overwhelming. But just think in terms of twos.

“Get two fruits and two vegetables of different colors, and two types of lean protein — such as fresh, frozen, or canned fish, chicken or lean ground turkey, or plant-based options,” suggests Nancy Oliveira, a registered dietitian and manager of the Nutrition and Wellness Service at Harvard-affiliated Brigham and Women’s Hospital.

Oliveira also recommends getting two foods in each of these categories on your weekly shopping trip:

• plant proteins, such as canned or dried beans, tofu, tempeh, veggie burgers, or unsalted nuts or seeds
• whole grains, such as whole-grain bread, whole-grain pasta, brown or black rice, quinoa, or farro
• dairy or nondairy milk items, such as nonfat Greek yogurt or cheese.

Go ahead and add one or two healthy treats or snacks, such hummus or dried apricots.

Do you need to choose organic foods?

Organic produce is grown without synthetic fertilizers and pesticides, which are linked to many health problems. While US scientists debate whether foods grown with organic fertilizers (such as animal waste) are safer for your health, other countries, including European Union nations, have banned or phased out synthetic pesticides still used in the United States.

That doesn’t mean that everything you buy must be organic. But try to stay away from conventionally grown produce with thin skins, such as strawberries, spinach, kale, peaches, and grapes. They tend to absorb more chemicals compared to produce with thick skins, such as avocados or pineapples.

The Environmental Working Group creates an annual list to help shoppers avoid high-pesticide produce, and another one that highlights the least contaminated produce.

Buying cost-conscious fresh food and staples

Healthy food, especially organic produce, has a reputation for being expensive. But it doesn’t have to be. Just do a little comparison shopping, and follow Oliveira’s tips to save money on a grocery run:

• Shop in a smaller store with fewer choices.
• Never enter a store hungry, since you might buy more than you normally would.
• Carry a shopping list and stick to it.
• Go directly to the aisles you need. Avoid browsing elsewhere, which may lead to extra purchases.
• Be flexible, have several options within your food categories, and go with sale items.
• Always check the day-old produce cart that offers perfectly edible fresh produce at 50% to 75% off regular prices.
• Buy unseasoned canned or frozen whole foods such as vegetables, chicken, or fish (salmon, sardines, tuna), which are often cheaper than fresh versions.
• Wait for sales of healthy nonperishable staples like quinoa, brown rice, whole-grain pasta, and high-fiber cereals.
• Use coupons and coupon apps.

Easy healthy snacks to reach for

Move on from easy grab-n-go snacks, which are typically processed foods. They often contain unhealthy ingredients and promote overeating. Instead, Oliveira suggests keeping healthy snacks on hand, such as:

• unsalted mixed nuts
• string cheese
• grapes and berries (rinse before eating)
• clementines, bananas, or other fruits that don’t need washing
• a rice cake with nut butter or hummus
• fat-free Greek yogurt
• a peeled hard-boiled egg.

“To save money, buy certain foods in larger amounts when possible, such as an 8-ounce bar of cheese that you slice into small cubes and store in a sealed container in the fridge,” Oliveira says.

Crowdsource shopping tips and savings

Don’t be shy about asking for shopping tips from friends and family members who’ve already developed shortcuts, and grocery store staffers who can offer insider advice.

You can also turn to apps for help. Oliveira recommends two faves:

• Mealime is a meal-planning app with simple, healthy plant-based recipes that automatically create grocery lists for the ingredients.
• List Ease creates lists for grocery runs. You can search for items to add or scan barcodes to add to lists.

“And if you prefer not to use apps, just jot down notes after a quick pantry or fridge inventory, or text yourself every time you remember something you need,” Oliveira advises. “With a little practice, you’ll quickly work out the best system for you.”

About the Author

Heidi Godman, Executive Editor, Harvard Health Letter

Heidi Godman is the executive editor of the Harvard Health Letter. Before coming to the Health Letter, she was an award-winning television news anchor and medical reporter for 25 years. Heidi was named a journalism fellow … See Full Bio View all posts by Heidi Godman

About the Reviewer

Howard E. LeWine, MD, Chief Medical Editor, Harvard Health Publishing

Howard LeWine, M.D., is a practicing internist at Brigham and Women’s Hospital in Boston, Chief Medical Editor at Harvard Health Publishing, and editor in chief of Harvard Men’s Health Watch. See Full Bio View all posts by Howard E. LeWine, MD