Our Better Health

Diet, Health, Fitness, Lifestyle & Wellness


Leave a comment

Selenium: What It Does and Where To Find It

Selenium Protects a Specific Type of Interneurons in The Brain

Exactly 200 years ago, the Swedish scientist Jöns Jacob Berzelius discovered the trace element selenium, which he named after the goddess of the moon, Selene. Besides its industrial applications (chemical industry, production of semiconductors and toners), selenium is an essential trace element and indispensable for humans, many animals and some bacteria. A team led by Dr. Marcus Conrad, research group leader at the Institute of Developmental Genetics (IDG) at Helmholtz Zentrum München, showed for the first time why selenium is a limiting factor for mammals.

Scientific ‘by-catch’ solves decades-old mystery

The scientists have been investigating for years the processes of a novel type of cell death, known as ferroptosis. In this context, the enzyme GPX4, which normally contains selenium in the form of the amino acid selenocysteine, plays an important role.

In order to better understand the role of GPX4 in this death process, we established and studied mouse models in which the enzyme was modified,” said study leader Conrad. “In one of these models, we observed that mice with a replacement of selenium to sulfur in GPX4 did not survive for longer than three weeks due to neurological complications.”

In their search for the underlying reasons, the researchers identified a distinct subpopulation of specialized neurons in the brain, which were absent when selenium-containing GPX4 was lacking. “In further studies, we were able to show that these neurons were lost during postnatal development, when sulfur- instead of selenium-containing GPX4 was present,” stated first author of the study, Irina Ingold.

Furthermore, the scientists were able to show that ferroptosis is triggered by oxidative stress, which is known to occur for instance during high metabolic activity of cells and high neuronal activity. “Our study demonstrates for the first time that selenium is an essential factor for the postnatal development of a specific type of interneurons,” said Dr. José Pedro Friedmann Angeli, a scientist at the IDG, describing the results. “Selenium-containing GPX4 protects these specialized neurons from oxidative stress and from ferroptotic cell death.”

Thus, the study explains why certain selenoenzymes are essential in some organisms, including mammals, whereas they are dispensable in other organisms, such as fungi and higher plants. In future investigations, study leader Marcus Conrad and his team aim to investigate how ferroptosis is triggered in cells. As a long-term goal, he wants to elucidate the role of ferroptosis in various disease conditions in order to be able to alleviate diseases, such as cancer or neurodegeneration, which are currently difficult to tackle.

Journal Reference:

Irina Ingold, Carsten Berndt, Sabine Schmitt, Sebastian Doll, Gereon Poschmann, Katalin Buday, Antonella Roveri, Xiaoxiao Peng, Florencio Porto Freitas, Tobias Seibt, Lisa Mehr, Michaela Aichler, Axel Walch, Daniel Lamp, Martin Jastroch, Sayuri Miyamoto, Wolfgang Wurst, Fulvio Ursini, Elias S.J. Arnér, Noelia Fradejas-Villar, Ulrich Schweizer, Hans Zischka, José Pedro Friedmann Angeli, Marcus Conrad. Selenium Utilization by GPX4 Is Required to Prevent Hydroperoxide-Induced Ferroptosis. Cell, 2017; DOI: 10.1016/j.cell.2017.11.048

Story Source:
Materials provided by Helmholtz Zentrum München – German Research Center for Environmental Health.
Note: Content may be edited for style and length.
December 29, 2017
www.sciencedaily.com

10 Foods Rich in Selenium

Selenium Function

This important nutrient is vital to immune system function. Selenium works in conjunction with vitamin E, vitamin C, glutathione and vitamin B3 as an antioxidant to prevent free radical damage in the body. It’s thought to help prevent cancer by affecting oxidative stress, inflammation and DNA repair. Selenium has been found to be important to male fertility; increasing selenium levels leads to improved sperm motility. There is preliminary research that suggests that selenium supplementation may also help with asthma symptoms, but more studies are needed.

Selenium Deficiencies

Deficiencies of selenium can occur in areas where soil content of this mineral is low. Diets high in refined foods may also lead to deficiency, as selenium can be destroyed by food processing. Taking anti-inflammatory drugs may reduce the body’s supply of selenium.

Low selenium levels can contribute to autoimmune problems, such as psoriasis and thyroid disease. Low levels have also been tied to stomach, throat and prostate cancers, although more research is needed to determine if this is a cause or a result of the disease. Some studies suggest that selenium deficiency is linked to mood disorders. There’s indication that deficiencies in selenium may contribute to the progression of viral infections.

10 Selenium Food Sources

The selenium content in foods depends on the concentration of selenium in the soil where the crops were grown. The following foods are generally considered good sources of selenium:

  • Brazil Nuts
  • Sunflower Seeds
  • Fish (tuna, halibut, sardines, flounder, salmon)
  • Shellfish (oysters, mussels, shrimp, clams, scallops)
  • Meat (Beef, liver, lamb, pork)
  • Poultry (chicken, turkey)
  • Eggs
  • Mushrooms (button, crimini, shiitake)
  • Grains (wheat germ, barley, brown rice, oats)
  • Onions

Recommended Daily Allowance

  • Children (under 3): 20 mcg
  • Children (4-8): 30 mcg
  • Children (9-13): 40 mcg
  • Adolescents (14-18): 55 mcg
  • Adults 19 and older: 55 mcg
  • Pregnant women: 60 mcg
  • Lactating women: 70 mcg

Toxicity

Exceeding 400 mcg per day can lead to selenium toxicity. Side effects may include hair loss, white spots on fingernails, fatigue, dizziness, nausea and nerve damage. There’s some evidence that high selenium levels may increase the risk of squamous cell skin cancer. Another well controlled study found a correlation between higher levels of selenium and an increased risk of developing type-2 diabetes.

Because of the possibility of toxicity, selenium supplements are controversial. The safest way to ensure a sufficient level of selenium in the diet is by eating a variety of selenium rich foods, like those listed above. Brazil nuts can be very high in selenium and should only be eaten occasionally. One Brazil nut can supply a whole day’s requirement of selenium, although this can vary depending on soil conditions. A multivitamin that contains some selenium is safe for most people to take and can help to fill the gap in a diet that is lacking.

source: www.fitday.com
Advertisements


Leave a comment

Selenium: What It Does and Where To Find It

Selenium Protects a Specific Type of Interneurons in The Brain

Exactly 200 years ago, the Swedish scientist Jöns Jacob Berzelius discovered the trace element selenium, which he named after the goddess of the moon, Selene. Besides its industrial applications (chemical industry, production of semiconductors and toners), selenium is an essential trace element and indispensable for humans, many animals and some bacteria. A team led by Dr. Marcus Conrad, research group leader at the Institute of Developmental Genetics (IDG) at Helmholtz Zentrum München, showed for the first time why selenium is a limiting factor for mammals.

Scientific ‘by-catch’ solves decades-old mystery

The scientists have been investigating for years the processes of a novel type of cell death, known as ferroptosis. In this context, the enzyme GPX4, which normally contains selenium in the form of the amino acid selenocysteine, plays an important role.

In order to better understand the role of GPX4 in this death process, we established and studied mouse models in which the enzyme was modified,” said study leader Conrad. “In one of these models, we observed that mice with a replacement of selenium to sulfur in GPX4 did not survive for longer than three weeks due to neurological complications.”

In their search for the underlying reasons, the researchers identified a distinct subpopulation of specialized neurons in the brain, which were absent when selenium-containing GPX4 was lacking. “In further studies, we were able to show that these neurons were lost during postnatal development, when sulfur- instead of selenium-containing GPX4 was present,” stated first author of the study, Irina Ingold.

Furthermore, the scientists were able to show that ferroptosis is triggered by oxidative stress, which is known to occur for instance during high metabolic activity of cells and high neuronal activity. “Our study demonstrates for the first time that selenium is an essential factor for the postnatal development of a specific type of interneurons,” said Dr. José Pedro Friedmann Angeli, a scientist at the IDG, describing the results. “Selenium-containing GPX4 protects these specialized neurons from oxidative stress and from ferroptotic cell death.”

Thus, the study explains why certain selenoenzymes are essential in some organisms, including mammals, whereas they are dispensable in other organisms, such as fungi and higher plants. In future investigations, study leader Marcus Conrad and his team aim to investigate how ferroptosis is triggered in cells. As a long-term goal, he wants to elucidate the role of ferroptosis in various disease conditions in order to be able to alleviate diseases, such as cancer or neurodegeneration, which are currently difficult to tackle.

Journal Reference:

Irina Ingold, Carsten Berndt, Sabine Schmitt, Sebastian Doll, Gereon Poschmann, Katalin Buday, Antonella Roveri, Xiaoxiao Peng, Florencio Porto Freitas, Tobias Seibt, Lisa Mehr, Michaela Aichler, Axel Walch, Daniel Lamp, Martin Jastroch, Sayuri Miyamoto, Wolfgang Wurst, Fulvio Ursini, Elias S.J. Arnér, Noelia Fradejas-Villar, Ulrich Schweizer, Hans Zischka, José Pedro Friedmann Angeli, Marcus Conrad. Selenium Utilization by GPX4 Is Required to Prevent Hydroperoxide-Induced Ferroptosis. Cell, 2017; DOI: 10.1016/j.cell.2017.11.048

Story Source:
Materials provided by Helmholtz Zentrum München – German Research Center for Environmental Health. 
Note: Content may be edited for style and length.
 
December 29, 2017

10 Foods Rich in Selenium

Selenium Function

This important nutrient is vital to immune system function. Selenium works in conjunction with vitamin E, vitamin C, glutathione and vitamin B3 as an antioxidant to prevent free radical damage in the body. It’s thought to help prevent cancer by affecting oxidative stress, inflammation and DNA repair. Selenium has been found to be important to male fertility; increasing selenium levels leads to improved sperm motility. There is preliminary research that suggests that selenium supplementation may also help with asthma symptoms, but more studies are needed.

Selenium Deficiencies

Deficiencies of selenium can occur in areas where soil content of this mineral is low. Diets high in refined foods may also lead to deficiency, as selenium can be destroyed by food processing. Taking anti-inflammatory drugs may reduce the body’s supply of selenium.

Low selenium levels can contribute to autoimmune problems, such as psoriasis and thyroid disease. Low levels have also been tied to stomach, throat and prostate cancers, although more research is needed to determine if this is a cause or a result of the disease. Some studies suggest that selenium deficiency is linked to mood disorders. There’s indication that deficiencies in selenium may contribute to the progression of viral infections.

10 Selenium Food Sources

The selenium content in foods depends on the concentration of selenium in the soil where the crops were grown. The following foods are generally considered good sources of selenium:

  • Brazil Nuts
  • Sunflower Seeds
  • Fish (tuna, halibut, sardines, flounder, salmon)
  • Shellfish (oysters, mussels, shrimp, clams, scallops)
  • Meat (Beef, liver, lamb, pork)
  • Poultry (chicken, turkey)
  • Eggs
  • Mushrooms (button, crimini, shiitake)
  • Grains (wheat germ, barley, brown rice, oats)
  • Onions

 

Recommended Daily Allowance

  • Children (under 3): 20 mcg
  • Children (4-8): 30 mcg
  • Children (9-13): 40 mcg
  • Adolescents (14-18): 55 mcg
  • Adults 19 and older: 55 mcg
  • Pregnant women: 60 mcg
  • Lactating women: 70 mcg

 

Toxicity

Exceeding 400 mcg per day can lead to selenium toxicity. Side effects may include hair loss, white spots on fingernails, fatigue, dizziness, nausea and nerve damage. There’s some evidence that high selenium levels may increase the risk of squamous cell skin cancer. Another well controlled study found a correlation between higher levels of selenium and an increased risk of developing type-2 diabetes.

Because of the possibility of toxicity, selenium supplements are controversial. The safest way to ensure a sufficient level of selenium in the diet is by eating a variety of selenium rich foods, like those listed above. Brazil nuts can be very high in selenium and should only be eaten occasionally. One Brazil nut can supply a whole day’s requirement of selenium, although this can vary depending on soil conditions. A multivitamin that contains some selenium is safe for most people to take and can help to fill the gap in a diet that is lacking.


1 Comment

The Nut That Protects Against Liver Cancer

When it comes to keeping the doctor away, apples could have some serious competition.

Based on new research, the adage could easily be changed to be “Two Brazil nuts a day keeps the doctor away.” That’s because according to the study, published in the American Journal of Clinical Nutrition, a deficiency in the mineral selenium is linked to a marked increase in liver cancer risk. And, you guessed it: Brazil nuts are an amazing source of selenium.

The researchers recognized that selenium deficiency is a widespread health concern that appears to be a risk factor for liver cancer and possibly other forms of cancer, although this study only examined the mineral deficiency’s effect on liver health. The researchers found that suboptimal selenium status may be linked to an appreciably increased risk of liver cancer—up to 10 TIMES the risk.

Eating a diet that contains adequate amounts of the mineral is not only critical to liver health and cancer prevention, it is also imperative to fertility and reproduction, thyroid hormone synthesis, immunity and DNA health. The mineral is also a potent antioxidant that helps to scavenge free radicals before they can damage the body’s cells and tissues.

Earlier studies in the journal Biomedical and Environmental Sciences show that adequate selenium intake also reduces skin cancer risk.

Some of the symptoms of selenium deficiency include: immune weakness, gastrointestinal (GI) problems, hair loss, diarrhea, cirrhosis, fatigue and mood swings. As with many nutritional deficiencies and medical conditions, there can be overlap in symptoms so having these symptoms does not necessarily mean you have a selenium deficiency. Conversely, if you have these symptoms you should consult your physician to rule out any other possible health conditions.

brazil-nuts

Selenium-Containing Foods

Oysters, tuna, whole grains, sunflower seeds, crimini mushrooms, poultry and eggs are all good sources of selenium; however Brazil nuts are by far the best. Just one ounce of these nuts (about 6-8) contains 544 micrograms of selenium. The recommended daily intake is 55 micrograms for adult males and females; however, pregnant and lactating women require 60 to 70 micrograms, respectively.

Selenium is also available in supplement form: as either selenomethionine or selenite. Selenomethionine is the more absorbable form of this mineral. Keep in mind that selenium can build up in tissues and can become harmful in excessive doses.

While an apple a day is still a good idea, you might want to add some Brazil nut butter or a handful of raw, unsalted Brazil nuts to round out the healing properties of this classic snack.

By: Michelle Schoffro Cook       @mschoffrocook       September 8, 2016
Dr. Michelle Schoffro Cook, PhD, DNM is an international best-selling and 20-time published book author whose works include: The Life Force Diet: 3 Weeks to Supercharge Your Health and Get Slim with Enzyme-Rich Foods.

 

source: www.care2.com


Leave a comment

Foods that can fix your health problems

By Sarah Richards, Health.com     Fri August 30, 2013

A regular breakfast of 100% whole grain cereal with fruit and low-fat milk is great. for maintaining mood balance.

(CNN) – Can’t sleep? Got the PMS blues? Before you open your medicine cabinet, step into your kitchen.

“Real, whole, fresh food is the most powerful drug on the planet,” says the author of “The Blood Sugar Solution” cookbook, Dr. Mark Hyman. “It regulates every biological function of your body.” In fact, recent research suggests not only what to eat but when to eat it for maximum benefit. Check out the latest smart food fixes.

Problem: I’m bloated

Food fix #1: Dig in to juicy fruits and vegetables

When you’re feeling puffy, you may not want to chow down on watery produce, but consuming foods like melon, cucumber and celery is an excellent way to flush out your system, says the author of the book “Food & Mood,” dietician Elizabeth Somer.
5 foods you should never eat

“We need sodium to survive,” she explains, “but because we often eat too much of it, our bodies retain water to dilute the blood down to a sodium concentration it can handle. Eating produce with high water content helps the dilution process, so your body can excrete excess sodium and water.”

Food fix #2: Load up on enzymes

Bloating can also be a sign that your intestines are out of whack. “If you’re irregular or experience gas right after eating, papaya can help,” explains the author of the book “Food as Medicine,” Dr. Dharma Singh Khalsa. “Eating 1 cup several times a week helps rejuvenate the gastrointestinal system, thanks to papaya’s digestive enzyme papain, which breaks down protein.”

The fiber also helps push food through your intestines, improving regularity. Try a smoothie with papaya, pineapple (it also contains digestive enzymes), protein powder, ice and almond milk.

Problem: I’m on an emotional roller coaster

Food fix #1: Say yes to breakfast

“People who eat within an hour or two of waking up have a more even mood throughout the rest of the day and perform better at work,” Somer says. British researchers found that study participants who skipped their morning meal did worse on memory tests and were more tired by midday than those who had eaten.

The optimal breakfast includes a whole grain to supply glucose for your brain to run on, protein to satisfy hunger and keep your blood sugar levels steady and one or two antioxidant-rich fruits or vegetables. Somer’s suggestion: a 100% whole-grain cereal that contains at least 4 grams of fiber and no more than 5 grams of sugar, eaten with fruit and low-fat milk.

Food fix #2: Stock up on selenium

A lesser-known trace mineral, selenium – found in Brazil nuts, tuna, eggs and turkey – helps keep you on an even keel. Women whose diets are deficient in the mineral are more prone to feeling depressed.

Why? Selenium is crucial for the production of thyroid hormones, which govern metabolism and mood. You don’t need much, though: The recommended daily allowance for selenium is 55 micrograms, and you can get that amount by eating one 3-ounce can of tuna.

Problem: My skin is acting up

The food fix: Eat your onions

Battling breakouts? The antioxidants in onions and other sulfur-rich veggies tamp down the inflammation that leads to acne, says Dr. Valori Treloar, a dermatologist in Newton, Massachusetts, and co-author of the book “The Clear Skin Diet.” The sulfur in onions, leeks and scallions helps produce a detoxifying molecule called glutathione, which a 2011 study found to be lower in the skin of people who were prone to breakouts.

This antioxidant is most potent when eaten in raw or lightly cooked foods. Try adding chopped scallions to your salad or stirring diced onions into your salsa or stir-fry. Taking folate and vitamin B6 and B12 supplements may also boost glutathione levels.


Problem: I get crazy-bad jet lag

The food fix: Don’t snack on the plane

It’s no fun spending the first days of your vacation trying to acclimate. One surprising secret to avoiding the headaches, irritability and upset stomach of jet lag is to fast for several hours before arriving at your destination. That’s because when you eat influences your circadian rhythms, in much the same way that exposure to light and dark does.

Let’s say you’re headed to France. On the plane, steer clear of most food (but drink plenty of water), set your watch to Paris time and eat a high-protein breakfast at 7 a.m., no matter where you are on your trip.

“The fast depletes your body’s energy stores, so when you eat protein the next morning, you get an extra kick and help your body produce waking-up chemicals,” explains Dave Baurac, spokesperson for the Argonne National Laboratory, a research institute based in Illinois.

Problem: I’m tossing and turning

Food fix #1: Have a late-night morsel

We’ve all been told to avoid eating too close to bedtime, but applying this rule too strictly could actually contribute to sleep woes. As anyone who has tried a fast knows, hunger can make you feel edgy, and animal studies confirm this.

“You need to be relaxed to fall asleep, and having a grumbling stomach is a distraction,” explains Kelly Glazer Baron, an instructor of neurology at Northwestern University and spokesperson for the American Academy of Sleep Medicine. “It makes it hard to get to sleep and wakes you up at night.”

The trick is to tame the munchies 30 minutes to an hour before bed with a small snack that includes complex carbohydrates. “Since you metabolize sugars more slowly at night, a complex carb like whole wheat is a better choice,” Baron says. “It keeps your blood sugar levels even.” Try cheese and whole-wheat crackers or almonds and a banana.

Food fix #2: Add cherries

You can boost your snack’s snooze power by washing it down with a glass of tart cherry juice. A recent study of folks with chronic insomnia found that those who downed 8 ounces of juice made from tart Montmorency cherries (available in most grocery stores) one to two hours before bedtime stayed asleep longer than those who drank a placebo juice.

These sour powerhouses – which you can eat fresh, dried or juiced – possess anti-inflammatory properties that may stimulate the production of cytokines, a type of immune-system molecule that helps regulate sleep. Tart cherries are also high in melatonin, a hormone that signals the body to go to sleep and stay that way.

Problem: I have wicked PMS

The food fix: Keep an eye on iron

You might be more susceptible to the monthly blahs if you have low levels of iron, according to a new study. Researchers looked at the diets of 3,000 women over 10 years and found that those who consumed more than 20 milligrams of the mineral daily had about a 40 percent lower risk of PMS than those who ingested less than 10 milligrams.

You can get almost your full daily dose by eating 1 cup of an iron-fortified cereal; other great sources include white beans (4 milligrams per one-half cup) and sautéed fresh spinach (3 milligrams per one-half cup).

The beta-carotene found in carrots is one of the most potent carotenoids and protects your skin from the sun.

Problem: I’m so sensitive to the sun

The food fix: Pile on protective produce

While you still need the usual sun protection (SPF 30 sunscreen as well as a wide-brimmed hat), you may be able to bolster your skin’s own resistance to UV rays with what you eat. The details: Micronutrients called carotenoids in fruits and vegetables protect the skin against sunburn, recent science shows.

“Most topical sunscreens work by filtering out the UV component from the solar light that reaches the skin,” explains researcher Wilhelm Stahl, a professor of biochemistry at Heinrich Heine University in Düsseldorf, Germany. “But these micronutrients, if you have enough in your system, actually absorb UV light and prevent damage.”

The most potent carotenoids are the beta-carotene found in carrots, endive and spinach – and the lycopene in watermelon and tomatoes. Keep in mind that the effect isn’t instantaneous; you would need to eat a carotenoid-rich diet for at least 10 to 12 weeks in order to get the full benefit, says Stahl. Still, there is a reward for your patience: skin fortified to fend off sun damage and wrinkles.