Omega-3 Supplements Do not Protect Against Cancer

Omega-3 fats do not protect against cancer – according to new research from the University of East Anglia.

Increased consumption of omega 3 fats is widely promoted globally because of a common belief that it will protect against, or even reverse, diseases such as cancer, heart attacks and stroke.

But two systematic reviews published today find that omega 3 supplements may slightly reduce coronary heart disease mortality and events, but slightly increase risk of prostate cancer. Both beneficial and harmful effects are small.

If 1,000 people took omega 3 supplements for around four years, three people would avoid dying from heart disease, six people would avoid a coronary event (such as a heart attack) and three extra people would develop prostate cancer.

The sister systematic reviews are published today in the British Journal of Cancer and the Cochrane Database of Systematic Reviews.

Omega 3 is a type of fat. Small amounts are essential for good health and can be found in the food that we eat including nuts and seeds and fatty fish, such as salmon.

Omega 3 fats are also readily available as over-the-counter supplements and they are widely bought and used.

The research team looked at 47 trials involving adults who didn’t have cancer, who were at increased risk of cancer, or had a previous cancer diagnosis, and 86 trials with evidence on cardiovascular events or deaths.

More than 100,000 participants were randomised to consume more long-chain omega-3 fats (fish oils), or maintain their usual intake, for at least a year for each of the reviews.

They studied the number of people who died, received a new diagnosis of cancer, heart attack or stroke and/or died of any of the diseases.

Lead author Dr Lee Hooper, from UEA’s Norwich Medical School, said: “Our previous research has shown that long-chain omega 3 supplements, including fish oils, do not protect against conditions such as anxiety, depression, stroke, diabetes or death.

“These large systematic reviews included information from many thousands of people over long periods. This large amount of information has clarified that if we take omega 3 supplements for several years we may very slightly reduce our risk of heart disease, but balance this with very slightly increasing our risk of some cancers. The overall effects on our health are minimal.

“The evidence on omega 3 mostly comes from trials of fish oil supplements, so health effects of oily fish, a rich source of long-chain omega 3, are unclear. Oily fish is a very nutritious food as part of a balanced diet, rich in protein and energy as well as important micronutrients such as selenium, iodine, vitamin D and calcium – it is much more than an omega 3 source.

“But we found that there is no demonstrable value in people taking omega 3 oil supplements for the prevention or treatment of cancer. In fact, we found that they may very slightly increase cancer risk, particularly for prostate cancer.

“However this risk is offset by a small protective effect on cardiovascular disease.

“Considering the environmental concerns about industrial fishing and the impact it is having on fish stocks and plastic pollution in the oceans, it seems unhelpful to continue to take fish oil tablets that give little or no benefit.”

Source: EurekAlert!

Ham & Cheese Croissant

Ingredients

1 croissant
2 thin slices cooked ham, halved mustard (optional)
2 slices hard cheese, such as Cheddar, Gruyere, or Emmental (about 1 oz)
1 egg, hard-cooked and sliced (optional)

Method

  1. Preheat the broiler on a medium–high setting.
  2. Slice the croissant horizontally in half, then lay it, cut sides up, on a piece of cooking foil on the rack in the broiler pan.
  3. Top each croissant with two half slices of cooked ham, overlapping the halves, and spread with a little mustard, if liked. Then top with the cheese, cutting and overlapping the slices to fit the croissant. Broil for about 2 minutes, until the cheese has melted. The croissant will be warmed through and beginning to brown around the edges.
  4. If including the egg, overlap the slices on the bottom half of the croissant. Use a knife to scoop any melted cheese off the foil and onto the croissant, then invert the top in place. Serve at once.

Makes 1 serving.

Source: Toast It!

In Pictures: Food of Afternoon Tea

Distrust of Past Experience May Underlie Obsessive-compulsive Symptoms

People with higher obsessive-compulsive symptoms may place less trust in their past experience, leading to increased uncertainty, indecisiveness, and exploratory behaviors, according to new research presented in PLOS Computational Biology by Isaac Fradkin of The Hebrew University of Jerusalem, Israel, and colleagues.

Obsessive-compulsive disorder (OCD) is characterized by intrusive thoughts, urges, or images that cause marked distress, and repetitive behavioral or mental rituals. For example, after turning off the lights, a person with OCD can easily become unsure whether the lights are off, and return repeatedly to check. Such behavior might reflect difficulty in trusting acquired experience, leading to an excessive need for gathering updated evidence.

To test that hypothesis, Fradkin and colleagues asked 58 people with varying levels of obsessive-compulsive symptoms to complete a decision-making task in which they had to balance the weight they assigned to prior experience with the weight given to more recent observations.

By defining the decision-making process with a set of mathematical equations, the researchers were able to show that participants with higher obsessive-compulsive symptoms indeed tended to distrust past experience, leading to a constant experience of the environment as unpredictable. These participants were also less able to predict the feedback they received for their choices, such that they were both more surprised by predictable feedback, and less surprised by unpredictable feedback.

“Our findings highlight a novel framework for understanding the cognitive and computational process that gives rise to obsessive compulsive symptoms,” Fradkin said. “The results also stand in stark contrast with the common preconception of OCD as being characterized by inflexible behavior, distinguished by overreliance on past experience.”

Unlike other OCD research that has focused on uncertainty, doubts, and indecisiveness, this study examined a more specific, well-defined process that could be defined mathematically. The new findings could contribute to the development of computational models that delineate the exact mechanisms leading to specific clinical symptoms, potentially informing the design of novel OCD treatments.

Source: Science Daily

Slow, Steady Increase in Exercise Intensity is Best for Heart Health — Much More is Not Always Much Better

For most people, the benefits of aerobic exercise far outweigh the risks, however, extreme endurance exercise – such as participation in marathons and triathlons for people who aren’t accustomed to high-intensity exercise – can raise the risk of sudden cardiac arrest, atrial fibrillation (a heart rhythm disorder) or heart attacks, according to a new Scientific Statement “Exercise-Related Acute Cardiovascular Events and Potential Deleterious Adaptations Following Long-Term Exercise Training: Placing the Risks Into Perspective–An Update from the American Heart Association,” published today in the Association’s premier journal Circulation.

Aerobic exercises are activities in which the large muscles move in a rhythmic manner for a sustained time. They can be done at low intensity or high intensity and include walking, brisk walking, running, bicycling, swimming and many others.

“Exercise is medicine, and there is no question that moderate to vigorous physical activity is beneficial to overall cardiovascular health. However, like medicine, it is possible to underdose and overdose on exercise – more is not always better and can lead to cardiac events, particularly when performed by inactive, unfit, individuals with known or undiagnosed heart disease,” said Barry A. Franklin, Ph.D., chair of the writing committee for the new Scientific Statement, director of preventive cardiology and cardiac rehabilitation at Beaumont Health in Royal Oak, Michigan, professor of internal medicine at Oakland University William Beaumont School of Medicine in Rochester, Michigan.

“More people are running marathons, participating in triathlons and doing high-intensity interval training. The purpose of this statement is to put the benefits and risks of these vigorous exercise programs in perspective,” said Franklin.

After reviewing more than 300 scientific studies, the writing committee found that, for the vast majority of people, the benefits of exercise and improving physical fitness outweigh the risks. Physically active people, such as regular walkers, have up to a 50% lower risk of heart attack and sudden cardiac death. However, the committee also identified potential risks with intense exercise training.

The writing group also reviewed a small study that concluded the risk of sudden cardiac death or heart attack is low among people participating in high-intensity exercise such as marathons and triathlons. However, over time, the risk of heart attack or sudden cardiac death among male marathon participants has risen, suggesting that these events are attracting higher risk participants (those who may have an underlying or undiagnosed cardiovascular condition such as heart rhythm abnormalities or a prior heart attack). For women, who comprised only 15% of the study population, the occurrence of sudden cardiac death was 3.5-fold less than in men.

Among participants in triathlons almost 40% of cardiac events occurred in first-time participants, indicating that inadequate training or underlying heart problems may be involved. The writing group also found that:

  • Half of cardiac events occur in the last mile of a marathon or half-marathon, so maintaining a steady pace rather than sprinting is advised;
  • The risk of cardiac events is greater at high altitudes, but can be decreased by spending at least one day acclimating to the elevation prior to strenuous activity;; and
  • Risk of atrial fibrillation (AFib), a common heart arrhythmia that raises the risk of stroke, is beneficially reduced with moderate exercise volumes but is highest in people who are sedentary and almost as high in people who are engaged in very high volumes of exercise training, that is, high-intensity training (such as running 60-80 miles a week).
  • For people who want to become more active, the Association suggests that most people can start a light program of exercise and build up slowly to a moderate to vigorous exercise regimen without seeing a physician first, unless they have physical symptoms such as chest pain, chest pressure or severe shortness of breath while exercising. “It is important to start exercising – but go slow, even if you were an athlete in high school,” said Franklin.

In addition, people with known heart disease (such as a previous heart attack, bypass surgery or angioplasty) should get their doctor’s approval prior to starting an exercise program.

For currently inactive/sedentary people, the Association also suggests checking with your doctor before engaging in any strenuous activities such as shoveling snow or racquet sports, which create rapid increases in heart rate and blood pressure and greatly increase the strain on the heart.

To implement a healthy physical activity program:

  • Warm up before exercise by doing the planned activity – such as walking – at a slower pace to let your heart rate rise gradually;
  • Walk on a level surface for 6-8 weeks, progressing to walking up hills, jogging or taking part in more vigorous activities as long as no symptoms occur such as shortness of breath, lightheadedness, chest pain or chest pressure;
  • Increase the amount of time spent on exercise incrementally from five to ten minutes at the beginning and build up slowly to the desired time;
  • Lower the intensity of your exercise when environmental conditions place a greater strain on the heart, such as high humidity or high altitude to which you are not accustomed;
  • Cool down after exercise by walking at a slow pace to let your heart rate return to normal; and
  • Stop and seek medical evaluation if you experience any heart-related symptoms such as lightheadedness, shortness of breath, or chest pain or pressure.

Source: American Heart Association


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