Cottonseed oil linked with rapid drops in triglycerides and cholesterol
Participants showed an average decrease of 8 percent in total cholesterol on the cottonseed oil diet, along with a 15 percent decrease in low-density lipoprotein, or LDL (the “bad” cholesterol) and a 30 percent decrease in triglycerides. (5 days)
Kristine R.Polley, Natalie J.Oswell, Ronald B.Pegg, Chad M.Paton, Jamie A.Cooper, A 5-day high-fat diet rich in cottonseed oil improves cholesterol profiles and triglycerides compared to olive oil in healthy men, Nutrition Research (2018). DOI: 10.1016/j.nutres.2018.09.001
2010 study posted for filing
Children and teens with higher blood levels of chemicals used in the production of non-stick cookware and waterproof fabrics appear more likely to have elevated total and LDL cholesterol levels, according to a report in the September issue of Archives of Pediatrics & Adolescent Medicine, one of the JAMA/Archives journals.
Humans are exposed to the man-made compounds known as perfluoroalkyl acids—including perfluorooctanoic acid (PFOA) and perfluorooctanesulfonate (PFOS)—through drinking water, dust, food packaging, breast milk, cord blood, microwave popcorn, air and occupational exposure, according to background information in the article. Recent national survey results reported detection of PFOA and PFOS in almost all samples of human serum. Perfluoroalkyl acids are used during the manufacture of fluoropolymers, which give non-stick heat resistance to cookware and breathable, waterproof properties to fabrics and upholstery. PFOA and PFOS may also result from the breakdown of compounds used as coating for commercial food packaging, factory treatments for fabrics and carpets and manufacturer pretreatment for stain-resistant clothing.
Animal studies have identified the liver as the primary organ affected by perfluoroalkyl acid exposure, with potential effects in human including alterations in cholesterol levels. Stephanie J. Frisbee, M.Sc., M.A., of West Virginia University School of Medicine, Morgantown, and colleagues assessed serum lipid levels in 12,476 children and adolescents (average age 11.1) included in the C8 Health Project, which resulted from the settlement of a class-action lawsuit regarding PFOA contamination of the drinking water supply in the mid–Ohio River Valley.
After enrolling in 2005 or 2006, the children and teens submitted blood samples; their average PFOA concentration was 69.2 nanograms per milliliter and average PFOS concentration was 22.7 nanograms per milliliter. Among 12- to 19-year old participants, PFOA concentrations were higher than those detected in a nationally representative survey (29.3 nanograms per milliliter vs. 3.9 nanograms per milliliter), but PFOS concentrations were similar (19.1 nanograms per milliliter vs. 19.3 nanograms per milliliter).
After adjusting for related variables, higher PFOA levels were associated with increased total cholesterol and LDL or “bad” cholesterol, and PFOS was associated with increased total cholesterol, LDL cholesterol and HDL or “good” cholesterol. There was no association between either compound and triglyceride levels.
On average, the one-fifth of children and teens with the highest PFOA levels had total cholesterol levels 4.6 milligrams per deciliter higher and LDL cholesterol levels 3.8 milligrams per deciliter higher than the one-fifth with the lowest PFOA levels. In addition, there was an average difference of 8.5 milligrams per deciliter in total cholesterol levels and 5.8 milligrams per deciliter in LDL cholesterol levels between the one-fifth of participants with the highest and lowest PFOS levels.
“The non-linear nature of the observed associations, particularly for PFOA, suggests a possible saturation point in an underlying physiologic mechanism,” the authors write. “PFOA and PFOS specifically, and possibly perfluoroalkyl acids as a general class, appear to be associated with serum lipids, and the association seems to exist at levels of PFOA and PFOS exposure that are in the range characterized by nationally representative studies.”
Although the design of the study limits cause-and-effect interpretations, the results suggest the association between PFOA and PFOS and elevated cholesterol levels warrant further study, the authors note. “Should the association prove to be etiologic, the cumulative effects of such an elevation in cholesterol on long-term cardiovascular health are unclear given the early age at which these associations were observed.”
(Arch Pediatr Adolesc Med. 2010;164:860-869. Available pre-embargo to the media at www.jamamedia.org.)
Editor’s Note: Please see the article for additional information, including other authors, author contributions and affiliations, financial disclosures, funding and support, etc.
2009 study posted for filing
AMES, Iowa — Research by an Iowa State University scientist suggests that cholesterol-reducing drugs known as statins may lessen brain function.
Yeon-Kyun Shin, a biophysics professor in the department of biochemistry, biophysics and molecular biology, says the results of his study show that drugs that inhibit the liver from making cholesterol may also keep the brain from making cholesterol, which is vital to efficient brain function.
“If you deprive cholesterol from the brain, then you directly affect the machinery that triggers the release of neurotransmitters,” said Shin. “Neurotransmitters affect the data-processing and memory functions. In other words — how smart you are and how well you remember things.”
Shin’s findings will be published in this month’s edition of the journal Proceedings of the National Academy of Sciences of the United States of America.
Cholesterol is one of the building blocks of cells and is made in the liver. Low-density lipoprotein (LDL) — often referred to as bad cholesterol — is cholesterol in the bloodstream from the liver on the way to cells in the body. High-density lipoprotein (HDL) — so-called good cholesterol — is cholesterol being removed from cells. Too much LDL going to cells and not enough being removed can lead to cholesterol deposits and hardening of the cells.
“If you have too much cholesterol, your internal machinery is not going to be able to take away enough cholesterol from the cells,” said Shin. “Then cells harden and you can get these deposits.”
Cholesterol-reducing statin drugs are helpful because they keep the liver from synthesizing cholesterol so less of the substance is carried to the cells. This lowers LDL cholesterol.
It is the function of reducing the synthesis of cholesterol that Shin’s study shows may also harm brain function.
“If you try to lower the cholesterol by taking medicine that is attacking the machinery of cholesterol synthesis in the liver, that medicine goes to the brain too. And then it reduces the synthesis of cholesterol which is necessary in the brain,” said Shin.
In his experiments, Shin tested the activity of the neurotransmitter-release machinery from brain cells without cholesterol present and measured how well the machinery functioned. He then included cholesterol in the system and again measured the protein function. Cholesterol increased protein function by five times.
“Our study shows there is a direct link between cholesterol and the neurotransmitter release,” said Shin. “And we know exactly the molecular mechanics of what happens in the cells. Cholesterol changes the shape of the protein to stimulate thinking and memory.”
While reducing the cholesterol in the brain may make you have less memory and cognitive skills, more cholesterol in the blood does not make people smarter. Because cholesterol in the blood cannot get across the blood brain barrier, there is no connection to the amount of cholesterol a person eats and brain function.
Shin says that for many people taking cholesterol-lower statins can be very healthful and they should listen to their doctor when taking medication.
A new national study has shown that nearly 75 percent of patients hospitalized for a heart attack had cholesterol levels that would indicate they were not at high risk for a cardiovascular event, according to current national cholesterol guidelines.
Specifically, these patients had low-density lipoprotein (LDL) cholesterol levels that met current guidelines, and close to half had LDL levels classified in guidelines as optimal (less than 100 mg/dL).
“Almost 75 percent of heart attack patients fell within recommended targets for LDL cholesterol, demonstrating that the current guidelines may not be low enough to cut heart attack risk in most who could benefit,” said Dr. Gregg C. Fonarow, Eliot Corday Professor of Cardiovascular Medicine and Science at the David Geffen School of Medicine at UCLA and the study’s principal investigator.
While the risk of cardiovascular events increases substantially with LDL levels above 40 mg/dL, current national cholesterol guidelines consider LDL levels less than 100� mg/dL acceptable for many individuals. The guidelines are thus not effectively identifying the majority of individuals who will develop fatal and non-fatal cardiovascular events, according to the study’s authors.
Researchers also found that more than half of patients hospitalized for a heart attack had poor high-density lipoprotein (HDL) cholesterol levels, according to national guidelines.
Published in the January issue of the American Heart Journal, the study suggests that lowering guideline targets for LDL cholesterol for those at risk for cardiovascular disease, as well as developing better treatments to raise HDL cholesterol, may help reduce the number of patients hospitalized for heart attack in the future.
“The study gives us new insight and intervention ideas to help reduce the number of heart attacks,” said Fonarow, who is also director of the Ahmanson–UCLA Cardiomyopathy Center.
“This is one of the first studies to address lipid levels in patients hospitalized for a heart attack at hospitals across the entire country.”
The research team used a national database sponsored by the American Heart Association’s Get with the Guidelines program. The database includes information on patients hospitalized for cardiovascular disease at 541 hospitals across the country.
Researchers analyzed data from 136,905 patients hospitalized for a heart attack nationwide between 2000 and 2006 whose lipid levels upon hospital admission were documented. This accounted for 59 percent of total hospital admissions for heart attack at participating hospitals during the study period.
Among individuals without any prior cardiovascular disease or diabetes, 72.1 percent had admission LDL levels less than 130 mg/dL, which is the current LDL cholesterol target for this population. Thus, the vast majority of individuals having their first heart attack would not have been targeted for effective preventative treatments based on the criteria used in the current guidelines.
The team also found that half of the patients with a history of heart disease had LDL cholesterol levels lower than 100 mg/dL, and 17.6 percent of patients had LDL levels below 70 mg/dL, which are guideline targets for LDL cholesterol in those at fair risk and at high risk for cardiovascular disease, respectively.
The study also showed that HDL cholesterol, or “good cholesterol,” levels have dropped in patients hospitalized for heart attack over the past few years, possibly due to increasing rates of obesity, insulin resistance and diabetes.
Researchers found that 54.6 percent of patients had HDL levels below 40 mg/dL. Developing more effective treatments to boost HDL levels may help reduce the number of patients hospitalized for heart attacks, according to the authors.
“We found that less than 2 percent of heart attack patients had both ideal LDL and HDL cholesterol levels, so there is room for improvement,” said Fonarow.
Fonarow said that only 59 percent of patients in the database had their lipid levels checked upon admission, which should be increased, since these early measurements can often help guide treatment decisions.
He also noted that only 21 percent of patients in the study were taking lipid-lowering medications before admission, despite almost half having a prior history of cardiovascular events, which would prompt treatment.
The national cholesterol guidelines are set by the National Cholesterol Education Program, part of the National Heart, Lung and Blood Institute of the National Institutes of Health.
The study was sponsored by the Get with the Guidelines program, which is supported by the American Heart Association in part through an unrestricted education grant from the Merck Schering Plough Partnership.
Fonarow has conducted research for GlaxoSmithKline and Pfizer and serves a consultant and has received honorarium from Abbott, AstraZeneca, GlaxoSmithKline, Merck, Pfizer and Schering Plough companies. He is also chair of the Get with the Guidelines steering committee.
Other authors include: Dr. Amit Sachdeva, Department of Medicine, David Geffen School of Medicine at UCLA, Los Angeles, CA; Dr. Christopher P. Cannon, Brigham and Women’s Hospital & Harvard Medical School, Boston, MA; Dr. Prakash C. Deedwania, Department of Cardiology, VA Medical Center/UCSF School of Medicine, San Francisco, CA; Dr. Kenneth A. LaBresh, Masspro, Waltham, MA; Dr. Sidney C. Smith, Jr., University of North Carolina School of Medicine, Chapel Hill, NC; David Dai, MS and Dr. Adrian Hernandez, Duke Clinical Research Institute, Durham, NC.
Abstract 6077; this abstract is also featured in a news conference
The neck arteries of obese children and teens look more like those of 45-year-olds, according to research presented at the American Heart Association’s Scientific Sessions 2008.
“There’s a saying that ‘you’re as old as your arteries,’ meaning that the state of your arteries is more important than your actual age in the evolution of heart disease and stroke,” said Geetha Raghuveer, M.D., M.P.H., associate professor of pediatrics at the University of Missouri Kansas City School of Medicine and cardiologist at Children’s Mercy Hospital. “We found that the state of the arteries in these children is more typical of a 45-year-old than of someone their own age.”
Researchers used ultrasound to measure the thickness of the inner walls of the neck (carotid) arteries that supply blood to the brain. Increasing carotid artery intima-media thickness (CIMT) indicates the fatty buildup of plaque within arteries feeding the heart muscle and the brain, which can lead to heart attack or stroke.
Investigators calculated CIMT in 34 boys and 36 girls who were “at-risk,” (average age 13, 89 percent white) and found:
- These children had abnormal levels of one or more types of cholesterol – elevated levels of low-density lipoprotein (LDL), which is known as “bad cholesterol;” low levels of high-density lipoprotein (HDL), which is the “good cholesterol;” or high triglyceride levels.
- Forty (57 percent) had a body mass index (BMI, a calculation of weight for height) above the 95th percentile.
Their average CIMT was 0.45 millimeters (mm), with a maximum of 0.75 mm.
The children’s “vascular age” — the age at which the level of thickening would be normal for their gender and race — was about 30 years older than their actual age, Raghuveer said.
The children were deemed at high risk for future heart disease because of obesity, abnormal cholesterol, and/or a family history of early heart disease.
On average, these children had:
- total cholesterol levels of 223.4 milligrams per deciliter (mg/dL) (less than 170 is considered acceptable by American Heart Association recommendations);
- LDL cholesterol levels of 149.8 mg/dL (less than 110 is considered acceptable); and
- triglycerides levels of 151.9 mg/dL (below 150 is considered acceptable).
Researchers found that having a higher BMI and higher systolic blood pressure had the most impact on CIMT.
Of the various risk factors, the children with triglycerides over 100 mg/dL were most likely to have an advanced vascular age. Thirty-eight children with high triglycerides had a CIMT above the 25th percentile for 45-year-olds, while only five in the group were below the 25th percentile. Children with lower triglycerides were evenly divided between those who scored below (13) or above (14) the 25th percentile on the charts for 45-year-olds.
“Vascular age was advanced the furthest in the children with obesity and high triglyceride levels, so the combination of obesity and high triglycerides should be a red flag to the doctor that a child is at high risk of heart disease,” Raghuveer said.
Further studies are needed to determine whether artery build-up will decrease if children lose weight, exercise, or are treated for abnormal lipids. Some studies have shown that CIMT can be reduced when children at extremely high risk are treated with cholesterol-lowering statin medications, and that exercise can improve blood vessel function in children with a high BMI.
“I’m optimistic that something can be done,” Raghuveer said. “In children, the buildup in the vessels is not hardened and calcified. We can improve the vessel walls and blood flow in adults through treatment, and I’m sure we can help children even more.”
Other risk factors for high CIMT in children are high blood pressure, exposure to secondhand smoke and insulin resistance – which is frequently seen in obese children.
Co-authors are: Joseph Le, medical student; Menees Spencer, medical student; David McCrary, M.D.; Danna Zhang, M.S.; and Chen Jie, Ph.D. Individual author disclosures are available on the abstract.
The Sarah Morrison Medical Student Research Grant from the University of Missouri, Kansas City, funded the research.
Editor’s note: In May 2005, the American Heart Association and the William J. Clinton Foundation formed the Alliance for a Healthier Generation. The alliance is working to reduce the nationwide increase in childhood obesity by 2010, and to empower kids nationwide to make healthy lifestyle choices. For more information visit: www.HealthierGeneration.org.
Statements and conclusions of study authors that are presented at American Heart Association scientific meetings are solely those of the study authors and do not necessarily reflect association policy or position. The association makes no representation or warranty as to their accuracy or reliability. The association receives funding primarily from individuals; foundations and corporations (including pharmaceutical, device manufacturers and other companies) also make donations and fund specific association programs and events. The association has strict policies to prevent these relationships from influencing science content. Revenues from pharmaceutical and device corporations are available at www.americanheart.org/corporatefunding.
2008 posted for filing
Low levels of LDL cholesterol as well as high levels are associated with cancer in patients with type 2 diabetes, found a prospective cohort study http://www.cmaj.ca/press/pg427.pdf published in CMAJ.
Researchers from the Hong Kong Institute of Diabetes and Obesity, the Li Ka Shing Institute of Health Sciences and The Chinese University of Hong Kong conducted a study of 6107 Chinese patients with type 2 diabetes and found a V-shaped risk relation between LDL cholesterol and cancer in patients not receiving statin therapy.
“LDL cholesterol levels below 2.80 mmol/L and levels of at least 3.90 mmol/L were both associated with markedly elevated risk of cancer among patients who did not use statins,” state Dr. Juliana Chan and coauthors.
The study excluded people on statins as statins obscured the association between LDL cholesterol and all-site cancer.
Increasing data suggests an association between type 2 diabetes and an elevated risk of cancer, including breast, colorectal, pancreatic and liver cancers. An elevated risk of cancer in patients with low LDL was linked to cancers of digestive organs and peritoneum, genital and urinary organs, lymphatic and blood tissues as well as other areas. Patients with an LDL cholesterol level above 3.80 mmol/L had heightened risks of oral, digestive, bone, skin, connective tissue, breast and other cancers.
Regarding clinical implications, the authors suggest “the use of these levels as risk markers may help clinicians to assess their patients more fully and thus to prevent premature deaths in patients who have high risk.”
They call for re-analysis of data from clinical trials to confirm or refute these findings.
In a related commentary, Drs. Frank Hu and Eric Ding of Harvard School of Public Health (Todd Datz, Public Relations, Harvard School of Public Health, 617-432-3952 for Dr. Frank Hu) say confounding factors such as indication for the use of statins, lifestyle and socioeconomic status must be considered when looking at the association of high levels of LDL cholesterol and the risk of cancer.
“Low serum cholesterol is commonly observed in individuals with ill health (e.g. cancer patients) and those with unhealthy lifestyle characteristics such as smoking and heavy drinking,” states Hu.