Wednesday, April 10, 2019

Healthy Eating for a Healthy Heart

Whether they take it hot or cold, black or “regular,” many people say they can’t live without it: Coffee. The dark, seductive beverage that has become a staple in the American diet. But when did we become so obsessed with coffee, and is our obsession, in fact, bad for us?

Researchers have some eye-opening answers.

The origins of coffee are unclear. One legend traces it back centuries ago to the forests of Ethiopia, where a goat herder discovered that his animals were energized after eating the red berries of the coffee bush. But wherever it started from, coffee’s popularity soon spread around the globe and eventually reached Europe and the “New World” by the 17th century.

Although tea was initially the beverage of choice for the American colonists, coffee eventually replaced it after the revolt against the taxation of tea by King George III, which culminated in the Boston Tea Party in December 1773. According to the National Coffee Association, Thomas Jefferson reportedly once described coffee as “the favorite drink of the civilized world.”

In modern times, a cup (or more) of brew has become a daily ritual in the US — with meals, at the office, in coffee shops, and at home. It’s available in every possible size and flavor combination, both with caffeine and without. But for years, experts have debated whether coffee promotes health or threatens it.
In search of coffee’s effects on health

Coffee contains antioxidants, which can help protect cells from damage. In some studies, coffee has been shown to have a protective effect against some cancers, as well as  chronic diseases like type 2 diabetes, Alzheimer’s, Parkinson’s, and gout. The caffeine in coffee is a stimulant and may help with mental alertness and fatigue.

However, too much coffee can make you jittery, lead to sleep problems, give you headaches, raise your blood pressure, and trigger heart arrhythmias, and it may even promote bone loss.  But is coffee really dangerous? Are coffee lovers putting their lives on the line when they reach for that next cup of java?

To investigate this further, scientists at the Harvard T.H. Chan School of Public Health looked at data from three ongoing studies involving almost 300,000 men and women for up to 30 years. The results of their research were recently published in the journal Circulation.

They found that moderate coffee consumption was actually associated with a lower risk of overall mortality, as well as a lower risk of death from heart and neurological diseases. Both caffeinated and decaffeinated coffee had a protective effect, suggesting that something other than caffeine is at play — perhaps those antioxidants. Heavier coffee drinking did not seem to further decrease the risk of death beyond that of moderate consumption, but it did not seem to increase the risk, either.

In the end, the researchers concluded, “Coffee consumption can be incorporated into a healthy lifestyle.”  Great news for the millions of Americans who need only be “dying” for coffee in the most metaphorical sense — and can happily live for it. People credit Eleanor Roosevelt as asking, “When will our consciences grow so tender that we will act to prevent human misery rather than avenge it?” Sadly, tenderness is still not a feature of every human conscience. So violence continues, often rationalized as revenge in response to misery caused by others.

Although altruism is often understood as rooted in tenderness, scientific research suggests otherwise. Rather, altruism may have evolved alongside the impulse to condemn and even punish those who act only in their own self-interests. We may be motivated to do good in order to avoid being shunned by our community.
The function of altruism

These impulses to act for the greater good may have helped our early ancestors enforce social norms, in a time before formal laws, contracts and courts compelled cooperation.

Years ago, a world-wide group of researchers, led by the anthropologist Joseph Henrich of Emory University in Atlanta, tested this theory. They created three experimental games and played them with people who lived in Africa, South America, New Guinea, the South Pacific and the American Midwest.

In these games, players were anonymous to one another. They were all given a real sum of money (or “stake”) to operate with:

    The Dictator game. Player A decides how much of their stake to give to player B. Player B has to accept whatever amount is offered. If player A is stingy, there is no punishment.
     The Ultimatum game. Player A decides how much to share with player B. Player B, before hearing the amount, decides what offer is acceptable. If B rejects A’s offer, both players get nothing.
     The Third Party Punishment game. Player A decides how much to share with player B. Player C is given a separate stake. If C feels A has been too stingy, C can punish A by reducing A’s winnings, but C must pay part of his or her stake for that privilege.

Self-interest dictates that all players should keep whatever money they’re given, since these are one-time, anonymous encounters and reputation doesn’t matter.

In fact, self-interest did not govern the results. Few people acted purely selfishly. Worldwide, there was an almost universal tendency to act altruistically and share the stake.

Player A usually offered something to player B and frequently gave away half. In the third party punishment game, player C was usually willing to sacrifice some money to punish selfishness. Player A, when aware that punishment was possible, tended to be more generous.

As player A got stingier, more players opted to punish him or her, whether they were the butt of player A’s selfishness or merely an onlooker. Local customs did affect the amount of sharing and the threshold for punishment.
Human values and norms

The studies don’t show whether punishment was induced by a desire for revenge, or from feelings of envy or competition. In any case, people may be more generous when they expect to be punished for selfishness that strays outside the cultural norm or where behaving fairly is a strong community value.

What does this mean for Eleanor Roosevelt’s longing for a universally tender human conscience? Humans with a greater capacity for altruism may have had a survival advantage in early societies. But so did people who were good with a spear or had a talent for foraging or farming. In evolutionary terms, being both strong and altruistic seems like the winning combination.

If pure altruism exists, Henrich’s study gives no proof of it. But it does support the notion that, even when we’re being “selfless,” we are serving our own interests.

Mrs. Roosevelt might argue that society becomes more livable when people feel good about being sympathetic and generous, rather than hard-hearted and ruthless. And if she could look around today, she probably would not think tenderness had flourished in the world since her death in 1962.

But she may be heartened to know about research that demonstrates “altruism” or conscience as a naturally emerging property of human societies. We humans do seem to have the capacity to play fair, even if we sometimes need the fear of punishment to help us do so. The yearly “check-up” is the perfect (perhaps only) time to not only see how kids are growing and give any needed shots, but to see how they are doing more generally — and help be sure that they grow into healthy, happy adults. After all, prevention is really what pediatrics is all about.

That’s why the American Academy of Pediatrics (AAP) has a checklist for pediatricians called “Recommendations for Preventive Pediatric Health Care.” These recommendations, which are updated every few years, are based on the most up-to-date research about the health of children now — and in the future.

While the latest version does include new recommendations for younger children, such as putting fluoride varnish on the teeth of children under 5 and doing a simple test for heart defects on newborns, most of the changes this time around pertain to adolescents. Here’s what the AAP thinks pediatricians should be doing with their pre-teen and teen patients:

    Lipid screening. Sometimes high cholesterol runs in families — but parents and other relatives may not have had theirs checked, or may not be aware of the test results of other family members. Because high cholesterol can cause real damage to blood vessels over time and lead to heart disease and stroke, it’s recommended that all youth have their cholesterol checked between the ages of 9 and 11. Doctors may do it before or again based on risk, but the AAP wants to be sure that everyone gets checked at least once.
    Screening for drug and alcohol abuse. As we all know, adolescents commonly experiment with drugs and alcohol. For some youth, this can lead to difficult or even deadly consequences. The AAP recommends asking six simple questions (called the CRAFFT screen) that can bring out really important information — and allow for really important conversations.
    Depression screening (for example, with a questionnaire). Suicide is a leading cause of death among adolescents — and depression is a treatable condition. But to treat it, we need to know that it’s there.
    HIV testing between the ages of 16 and 18. This is important because one in four new HIV infections occurs in youth ages 13 to 24, and 60% of all youth with HIV don’t know they are infected. If they don’t know, not only can they not get help, but they can spread the infection to others.

I can imagine some parents saying, “My child doesn’t need these — our family is healthy and my child is a good, happy kid who knows to stay out of trouble.” But the simple truth is that we can never know everything about either our family history or our child — and when it comes to the health and well-being of our children, it’s always better to be safe than sorry. Prenatal yoga is typically gentle, with certain poses modified or avoided depending on the stage of pregnancy. But a new study, published recently in the journal Obstetrics & Gynecology, provides encouraging results that many yoga poses can be safe even during late stages of pregnancy.
Testing the safety of various yoga poses

For the study, the researchers invited 25 women between 35 and 38 weeks of pregnancy to take part in a yoga session. They included women with previous yoga experience as well as those who were new to the practice. All of the women were generally healthy and free of pregnancy-related or other health issues like high blood pressure or gestational diabetes.

The yoga session consisted of 26 poses, including some (such as Happy Baby pose and Corpse pose) that are often avoided during pregnancy. Several poses, including balancing poses like Half Moon, Warrior III, and Tree, were modified by using blocks, chairs, or a wall.

During the session, the researchers monitored each woman’s blood pressure, heart rate, temperature, oxygen levels, and uterine contractions, as well as the fetal heart rate — a measure of a baby’s well-being. All vital signs of both mother and baby were normal during the poses and after the session. There were no falls, injuries, or safety problems.

The researchers also followed up with each participant via email 24 hours after the session. All the women reported feeling safe during the yoga poses. None of them had any problems later with contractions, vaginal bleeding, or reduced movement of the baby. All of the women, except three who described muscle soreness, expressed only positive experiences with the yoga session. The researchers concluded that the 26 different yoga poses — including those that were previously avoided — were safe for both the mothers-to-be and their babies.

Here is a list of the 26 poses from the study. The poses marked with an asterisk (*) were previously thought to be contraindicated during pregnancy.
1.     Easy pose, Sukhasana

2.     Seated forward bend, Paschimottanasana

3.     Cat pose, Marjaryasana

4.     Cow pose, Bitlasana

5.     Mountain pose, Tadasana

6.     Warrior I, Virabhadrasana I

7.     Standing forward bend, Uttanasana

8.     Warrior II, Virabhadrasana II

9.     Chair pose, Utkatasana

10.  Extended side angle pose, Utthita Parsvakonasana

11.  Extended triangle pose, Utthita Trikonasana

12.  Warrior III, Virabhadrasana III

13.  Upward salute, Urdhva Hastasana
    14.  Tree pose, Vrksasana

15.  Garland pose, Malasana

16.  Eagle pose, Garudasana

17.  Downward-facing dog, Adho Mukha Svanasana*

18.  Child’s pose, Balasana*

19.  Half moon pose, Ardha Chandrasana

20.  Bound angle pose, Baddha Konasana

21.  Hero pose, Virasana

22.  Camel pose, Ustrasana

23.  Leg up wall pose, Viparita Karani

24.  Happy baby pose, Ananda Balasana*

25.  Half Lord of the fishes pose, Ardha Matsyendrasana

26.  Corpse pose, Savasana*

This study suggests that yoga can be safe during late pregnancy and adds to the growing scientific evidence that yoga is a helpful, safe tool to reduce stress, anxiety, and depression throughout pregnancy. Over half of all women experience anxiety at some point during pregnancy, and about 13% of pregnant women experience clinical depression. Yoga has been shown to ease stress and anxiety during pregnancy and to reduce levels of the stress hormone cortisol. Several studies of yoga during pregnancy have found it is also effective for reducing depression, particularly when it is started early in the pregnancy and can be combined with standard depression treatment. Yoga can also reduce pain and discomfort, as well as improve overall quality of life during pregnancy.

Prenatal yoga is particularly effective as part of an integrated approach that includes breathing exercises, meditation, and deep relaxation.
How to make the most of yoga during pregnancy

Moms-to-be should focus more on stability and strength, rather than endurance and flexibility. Use modifications, props, or a wall to make each pose well-supported. Pregnancy hormones loosen your muscles and ligaments, which increases the risk for injuries if you push yourself too far in terms of flexibility. This is true even in the first trimester. Another hormone called relaxin, which is at its highest levels in the first trimester and relaxes muscles, tendons, and ligaments, also peaks in the first trimester. This laxity means you can accidentally over-stretch your joints and muscles.

Finally, some forms of yoga done in extreme heat, like Bikram yoga, where the room can be up to 105 degrees Fahrenheit, are not recommended during pregnancy. There are currently no studies that can tell us whether heated yoga is safe for pregnant women. But we do know heated yoga tends to raise core body temperature, which can pose significant risks for both mother and baby. Heat also loosens ligaments further and increases the risk of overheating and dehydration. Recently, a Harvard Heart Letter subscriber emailed us a question: Is there a difference between farm-raised and wild-caught salmon in terms of omega-3 fatty acid content?

I’ve wondered about this myself while standing at the fish counter at my local grocery store. I can often find farm-raised Atlantic salmon for about $6.99 a pound, while the wild-caught salmon may be nearly twice as expensive. Salmon and other fatty fish are the main dietary source for omega-3 fatty acids, which are known to lower the risk of heart disease.

It turns out that you probably won’t shortchange your heart if you choose the less-costly farmed salmon, as both types seem to provide similar amounts of omega-3s per serving. But that’s likely because farm-raised salmon tend to have more total fat — and therefore more omega-3 fat — than wild ones.
How the total fat content of salmon measures up

As Dr. Bruce Bistrian, professor of medicine at Harvard Medical School, explained to me, fish are what they eat. “In the wild, salmon eat smaller fish that are high in EPA and DHA — the beneficial, long-chain omega-3 fatty acids.” Farm-raised salmon eat high-protein food pellets. While location and environmental changes can affect the diet of a wild salmon, the flesh of a farmed fish reflects the farmer’s choice of pellets. In particular, farmers often feed the young salmon pellets made from plant and animal sources, then add the more expensive fish- and fish-oil–enriched pellets later in the fish’s lifespan.

A study that measured fatty acids in 76 different fish species from six regions of the United States found big variations in the omega-3 content in the five different salmon species tested — especially the two farm-raised varieties. The omega-3 content ranged from 717 milligrams (mg) to 1,533 mg per 100 grams of fish (equal to a “standard” 3.5-ounce serving). Compared to the wild-caught varieties, farmed fish tended to have higher levels of omega-3s, but they also contained higher levels of saturated and polyunsaturated fats. But the amount of saturated fat isn’t alarming. For comparison, a serving has about 1.6 grams, which is about half as much in the same amount of flank steak.
The best choices for salmon — and the rest of your plate

Bottom line: Don’t stress too much about your salmon selection. Follow the American Heart Association’s advice to eat two servings of fish a week, letting affordability and availability guide your choices. As for me, I often opt for farmed salmon for dinner once a week or so, but I’ll splurge on wild salmon if it looks especially good. When I have canned tuna, I look for the “chunk light” variety, which is lower in mercury than other varieties. (For more on that topic, see one of my previous blogs). Other good fatty fish choices include sardines, herring, bluefish, and mackerel.

And don’t forget to keep the big picture in mind when choosing what to eat. Nutrition experts like Dr. Bistrian stress that much of the most compelling evidence about a heart-healthy eating patterns comes from studies of the Mediterranean diet, which includes fish as well as lots of fruits and vegetables, whole grains, nuts and olive oil but minimal amounts of meat and dairy. “If you eat more fish in the context of other changes in your diet, that’s more likely to confer a benefit,” says Dr. Bistrian.

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