Study: Sunscreen Chemicals Enter Bloodstream at Potentially Unsafe Levels

Dennis Thompson wrote . . . . . . . . .

For years, you’ve been urged to slather on sunscreen before venturing outdoors. But new U.S. Food and Drug Administration data reveals chemicals in sunscreens are absorbed into the human body at levels high enough to raise concerns about potentially toxic effects.

Bloodstream levels of four sunscreen chemicals increased dramatically after test subjects applied spray, lotion and cream for four days as directed on the label, according to the report.

The levels far exceed the FDA-set threshold which require topical medications to undergo safety studies, said Dr. Kanade Shinkai, a dermatologist with the University of California, San Francisco School of Medicine.

“It’s not like they went a little bit over,” she said. “It’s really quite high, orders of magnitude higher than that.”

However, experts are quick to say you shouldn’t stop using sunscreen because of this study. At this point, the known risk of harm from the sun’s rays exceeds the potential risk posed by these chemicals.

“I am concerned that people are going to stop wearing sunscreen,” Shinkai said. “We know ultraviolet light from the sun has very deleterious effects on the skin. It causes photoaging. It causes sunburn. And, as such, it causes melanoma and [other] skin cancer.”

Dr. Michele Green, a dermatologist with Lenox Hill Hospital in New York City, agreed.

“I think it’s confusing,” Green said. “While it’s more than the FDA recommends for their toxicology, we really don’t know what that means in terms of human health. I would not want people to stop using sunscreen based on this one study.”

Possible effects on hormones

The sunscreen study was led by the FDA’s Dr. David Strauss, and appears May 6 in the prestigious Journal of the American Medical Association, one of the nation’s leading medical journals.

Most sunscreens on the shelf use chemicals such as oxybenzone, avobenzone and octocrylene to block harmful rays. These organic chemicals absorb ultraviolet radiation and convert it into a small amount of heat.

However, animal studies have raised concerns that the chemicals, oxybenzone in particular, might disrupt normal hormone patterns in people, the FDA researchers noted in their study.

“These molecules are chemical rings, essentially, and they absorb light,” said Shinkai, who co-wrote an editorial accompanying the study. “Chemical rings are also the fundamental basis for a lot of hormones, and chemical rings tend to enter cells.”

Oxybenzone has been found in human breast milk, amniotic fluid, urine and blood, the FDA researchers said.

For its study, the FDA randomly had 24 adults apply either a sunscreen spray, lotion or cream four times a day for four days. The participants applied the sunscreen to three-quarters of their body surface.

The study took place in a lab, and the agency drew 30 blood samples from each participant over a week to see whether the chemicals in the sunscreen got absorbed through the skin.

Levels of oxybenzone, avobenzone, octocrylene and ecamsule increased in the bloodstream after sunscreen use, researchers found.

“There is definitely reason for concern, because if you think about it, any medication you buy over the counter, you would expect that everything in there has been tested, it’s safe, it’s effective,” Shinkai said. ‘This has never been proven for sunscreen.”

More real-life data needed

But it was a very small-scale laboratory study that simply shows the need for more research, said Dr. Raman Madan, a dermatologist with Northwell Health’s Huntington Hospital in Huntington, N.Y.

“While this is a starting point, the relevance of this result is unknown,” Madan said. “There needs to be further studies done to show what this really means. While it could have real-world consequences, it could very well mean nothing.”

The study also differs from real life in that people applied the sunscreen while hanging about a lab, Shinkai said.

“They weren’t doing the things people typically do when they use sunscreen,” such as swimming or working in the yard, Shinkai said. Because of this, their exposure might differ from that of everyday people.

The Consumer Healthcare Products Association (CHPA), a group representing sunscreen makers, also said it’s far too soon for consumers to have doubts about these products.

“Sunscreen manufacturers, FDA, and dermatologists are aligned on the goal of protecting the public from the harmful effects of the sun,” the group said in a statement. “Sunscreens save lives.”

CHPA said the FDA is committed to learning more about the safety of chemicals within sunscreens, however, and the new data “is consistent with these efforts.”

Options are out there

The FDA has been tussling with sunscreen manufacturers over studies to test the safety of their products, said Shinkai.

The agency has set a November 2019 deadline for manufacturers to provide safety data on their sunscreens, including evaluations of systemic absorption, the risk of cancer from the chemicals, and their effect on reproductive health, Shinkai said in her editorial.

The publication of this study might be intended to put pressure on the sunscreen industry to meet the deadline, she said.

“The FDA is a regulatory agency. It’s not a testing agency. For them to perform a research study is highly unusual,” Shinkai said. “I think that’s an important thing that suggests how concerned they were about this issue, and maybe perhaps the frustration on their part.”

People who are concerned about the safety of chemical sunscreens can opt to use mineral sunscreens, Shinkai said.

Those sunscreens rely on zinc oxide and titanium dioxide to reflect sunlight from the skin, rather than absorbing it like chemical sunscreens.

“These we know are safe,” Shinkai said of mineral sunscreens. “This is something that is evidence-based.”

Source: HealthDays


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MCH Levels in Blood Tests: What Do They Mean?

Jon Johnson wrote . . . . . .

To determine MCH levels in the blood, a doctor may order a CBC test.

MCH stands for mean corpuscular hemoglobin.

MCH levels refer to the average amount of hemoglobin found in the red blood cells in the body. Hemoglobin is a protein in the blood that allows red blood cells to deliver oxygen to the cells and tissues in the body.

Though they are very similar, MCH levels should not be confused with MCHC levels.

MCH levels are the average amount of hemoglobin that is in each red blood cell. MCHC levels are the average weight of that hemoglobin based on the volume of red blood cells. Both are a reflection of the health of the hemoglobin in the blood.

What is a CBC test?

A complete blood count test, or simply CBC test, is designed to give doctors a general overview of a person’s health. The test can help screen people for a variety of issues at once and may help diagnose conditions, such as bleeding disorders, infections, and anemia.

Regular health screenings will often include a CBC test. If the results come back normal, the person may not need another test until their next health screening. Doctors may order CBC tests if a person shows signs of any disorder that can affect the blood.

A CBC test can also be used to help monitor individuals who have blood disorders. Doctors will use them to track the progress of a treatment and determine how effective it is.

CBC tests examine all three types of cells in the blood. The test will give a total white, red, and platelet cell count.

CBC tests examine all three types of cells in the blood and will show the total number of white cells, red cells, and platelets in the blood.

MCH levels

Doctors will often order a CBC test to find out a person’s MCH levels. Normal MCH levels are around 27 to 33 picograms (pg) per cell in adults. These numbers may vary based on the machine used to carry out the test.

The numbers are different in young children. A person with a low MCH has concentrations at or below 26 pg per cell. A person with high MCH levels will have concentrations at 34 pg per cell or more.

Causes of low MCH levels

Different types of anemia can cause low MCH levels. For example, microcytic anemia occurs when the blood cells are too small and cannot take in as much hemoglobin as they should. This can be due to malnutrition or nutritional deficiencies.

Some medical conditions can also cause anemia, even if the person eats a balanced and healthful diet.

Low amounts of iron in the blood can also cause low MCH levels. The body uses iron to make hemoglobin. If the body runs out of iron, iron deficiency anemia can cause low MCH levels. This type of anemia may be more common in vegetarians or people with poor nutritional intake.

People with other conditions may also experience low MCH levels. Celiac disease can prevent the body from properly absorbing iron, which makes it very difficult to keep the iron levels where they need to be.

Likewise, people who have had types of gastric surgery may also not be able to absorb iron as well as they need to. Women with excessive menstruation may also become anemic, as they lose more iron in the menstrual blood than they can recover.

Low MCH levels can also appear in a body that is lacking key vitamins. People who do not get enough B vitamins such as folate and B12 may show low MCH concentrations on their tests. Because a lack of vitamins can also show high MCH levels, doctors may request further lab testing and interpretation to make a definitive diagnosis.

Symptoms of low MCH levels

At first, many people with low MCH levels do not experience symptoms at all. When low MCH numbers persist or fall too low, symptoms start to appear. Symptoms of low MCH include:

  • shortness of breath
  • loss of regular stamina
  • consistent tiredness
  • dizziness
  • weakness in the body

Low MCH numbers can also affect the skin. The skin may become pale or bruise very easily in someone with low MCH levels.

Anyone experiencing these symptoms should contact their doctor immediately.

Causes of high MCH levels

High MCH scores are commonly a sign of macrocytic anemia. This condition occurs when the blood cells are too big, which can be a result of not having enough vitamin B12 or folic acid in the body.

High MCH scores may also be the result of the following:

  • liver diseases
  • an overactive thyroid gland
  • drinking alcohol regularly
  • complications from certain cancers
  • complications from an infection
  • taking too many medications containing estrogen

Symptoms of high MCH levels

People experiencing a high MCH caused by macrocytic anemia may experience symptoms that follow a particular pattern. People may not notice symptoms at first, but they can gradually get worse over time. Symptoms of high MCH include:

  • tiredness
  • very pale skin
  • fast heartbeat
  • nails that are brittle and easily broken
  • brain fog or poor concentration
  • confusion and memory loss

People with macrocytic anemia may also experience digestive issues. They may not have an appetite, lose weight, and have regular diarrhea. A person experiencing any of these symptoms should talk to their doctor as soon as possible.

Treatment for MCH level imbalance

How doctors treat unbalanced MCH levels can vary with every case. Treatment largely depends on treating the cause of the imbalance.

Adding more vitamin B12 and folic acid to the diet can be a good way to address high MCH levels. It is best to get these from a varied and balanced diet, but supplements may also help keep these levels where they need to be.

Low MCH levels usually occur as a result of iron deficiency that has led to anemia. Doctors may recommend that individuals add more iron and vitamin B6 to their diet. Eating vitamin C and fiber, along with foods that contain iron, may also help increase the MCH levels.

People with an imbalance in their MCH levels should always discuss a treatment plan with their doctors before taking any supplement or making drastic changes to their diet.

Source: Medical News Today

High Blood Sugar May Boost Alzheimer’s Risk

Insulin resistance can inhibit signaling between brain cells and affect memory, study suggests.

High blood sugar associated with prediabetes may increase the risk for Alzheimer’s disease, a new study suggests.

Researchers found that insulin resistance — higher-than-normal levels of blood sugar that often precede type 2 diabetes — was related to poorer performance on memory tests taken by late-middle-age adults.

“The findings are interesting because people with diabetes are at increased risk for developing Alzheimer’s disease, but we are only now learning why they may be at increased risk,” said lead researcher Barbara Bendlin, an assistant professor of medicine at the University of Wisconsin-Madison.

The study results suggest that insulin resistance could increase the risk for Alzheimer’s disease by altering the way the brain uses sugar (glucose), which is its primary fuel, she said.

However, “by altering insulin resistance in midlife, it may be possible to reduce future risk of Alzheimer’s disease,” Bendlin said. Medications and a healthy lifestyle are possible ways to do that, she said.

According to the American Diabetes Association, 29.1 million Americans have diabetes, and more than half of adults older than 64 have prediabetes. Poor diet, obesity and sedentary lifestyles are associated with insulin resistance, Bendlin noted.

“Healthier lifestyles may contribute to healthier brain aging by reducing insulin resistance,” Bendlin said.

One expert cautioned that having prediabetes, or insulin resistance, doesn’t mean you’re doomed to develop Alzheimer’s, the most common form of dementia.

This study shows that insulin resistance may make mental functioning worse and may be linked to reduced use of insulin in areas of the brain associated with Alzheimer’s disease, but this does not mean that insulin resistance leads to Alzheimer’s, said Dr. Luca Giliberto, an investigator at the Litwin-Zucker Research Center for the Study of Alzheimer’s Disease at the Feinstein Institute for Medical Research in Manhasset, N.Y.

“We do not know what causes Alzheimer’s disease,” said Giliberto, who was not involved in the study. “We don’t know if lowering blood sugar will prevent Alzheimer’s.”

For the study, Bendlin’s team gave memory tests to 150 adults with no mental impairments, at average age of 61. The researchers also measured insulin resistance and had the participants undergo a PET brain scan.

More than two-thirds of the participants had a parent who suffered from Alzheimer’s, about 40 percent had a gene mutation associated with increased Alzheimer’s risk and roughly 5 percent had type 2 diabetes, according to the study.

The researchers found insulin resistance was associated with poorer processing of sugar throughout the brain. Worse performance in immediate memory was linked to lower sugar metabolism in the left medial temporal lobe, the authors said.

The report was published online in JAMA Neurology.

Dr. Sam Gandy, director of the Center for Cognitive Health at Mount Sinai Hospital in New York City, said it appears there may be a difference “between the dementia related to full-blown diabetes, which seems to be primarily dementia caused by hardening of the arteries in the brain, and the mental impact of insulin resistance, which some investigators believe is associated with Alzheimer’s.”

In the brain, insulin helps transmit messages between cells, he noted.

“We have long thought of Alzheimer’s as a disease of defective brain signaling,” said Gandy, who had no role in the study. “Conceivably, there is also a disease of defective insulin signaling, which this paper would support.”

If that’s true, Gandy added, “then efforts at sensitizing the brain to insulin, using drugs such as pioglitazone [Actos, a diabetes drug], would make sense and might well lead to slowing of degeneration.”

Giliberto recommended healthy living as the best way to keep blood sugar under control and perhaps protect mental health.

“Increasing our health by reducing fats, reducing sugar, improving insulin resistance may reduce the risk of other factors, such as diabetes, on the susceptibility to Alzheimer’s disease and mental decline,” Giliberto said

Source: U.S. Department of Health and Human Services

Study Shows High Blood Calcium Levels May Indicate Ovarian Cancer

Study Shows High Blood Calcium Levels May Indicate Ovarian Cancer

A new study from Wake Forest Baptist Medical Center is the first to report that high blood calcium levels might predict ovarian cancer, the most fatal of the gynecologic cancers.

Lead author Gary G. Schwartz, Ph.D., a cancer epidemiologist at Wake Forest Baptist, and colleague, Halcyon G. Skinner, Ph.D., of the University of Wisconsin Carbone Cancer Center, examined associations between blood calcium and ovarian cancer in two national population-based groups. They found that women who were later diagnosed with ovarian cancer and women who later died of ovarian cancer had higher levels of calcium in blood than women who did not before their cancer diagnosis.

Schwartz, who is well-known for his epidemiologic research in prostate cancer, said the idea for this study came about because of published research from his group which showed that men whose calcium levels were higher than normal have an increased risk of fatal prostate cancer. That led him to wonder if a similar relationship were true of ovarian cancer.

“One approach to cancer biomarker discovery is to identify a factor that is differentially expressed in individuals with and without cancer and to examine that factor’s ability to detect cancer in an independent sample of individuals,” Schwartz said. “Everyone’s got calcium and the body regulates it very tightly,” Skinner added. “We know that some rare forms of ovarian cancer are associated with very high calcium, so it’s worth considering whether more common ovarian cancers are associated with moderately high calcium.”

The idea is plausible, Schwartz explained, because many ovarian cancers express increased levels of a protein, parathyroid hormone-related protein (PTRHrP), which is known to raise calcium levels in blood in many other cancers.

Ovarian cancer has a high fatality rate because it is hard to detect and by the time symptoms arise, the cancer is usually advanced. Schwartz said early diagnosis might be accomplished through the use of a calcium biomarker, but cautions that more research is needed to confirm these results. “We found the link between serum calcium and ovarian cancer; we confirmed it, and even though the study is small, we’re reporting it because it’s a very simple thing in theory to test.”

The study is published online this month in the journal Gynecologic Oncology.

Source: Wake Forest Baptist Medical Center

Blood Test May Spot Serious Health Risks in Women

A new blood test may help identify a woman’s risk of developing heart disease, diabetes and breast cancer, a new study suggests.

The test, which measures levels of a substance called proneurotensin, may also spot an increased risk of early death, the researchers behind the study said.

“In women, but not in men, there were very strong relationships between high concentrations of proneurotensin in the blood and the risk of developing diabetes, cardiovascular disease and breast cancer,” said the study’s lead author, Dr. Olle Melander, professor of internal medicine at Lund University in Malmo, Sweden.

“Women with high levels of proneurotensin in the blood died significantly earlier than women with normal proneurotensin concentrations, and the excess mortality with high proneurotensin was primarily caused by cardiovascular diseases,” added Melander.

Results of the study are published in the Journal of the American Medical Association.

Proneurotensin is a precursor of neurotensin, a hormone produced in the brain and in the digestive system that is secreted during meals — particularly high-fat meals. Neurotensin has a number of jobs in the body: It helps with food digestion, the regulation of body temperature and the sensation of pain, and is also involved in the regulation of appetite and feelings of fullness, Melander said.

In several recent studies, the hormone has also been linked to heart disease risk and to the growth of breast cancer tissue, said Melander.

But neurotensin levels are very difficult to measure. Proneurotensin, its precursor, however, is a stable indicator of the production and secretion of neurotensin, Melander explained.

The researchers hypothesized that the neurotensin system might play a role in the development of diseases related to excess weight, which include diabetes, breast cancer and heart disease.

Read more ….