4/11/23
Treating a heart attack before it happens: It may not be a science fiction
By Hannah Flynn on March 20, 2023 — Fact checked by Jill Seladi-Schulman, Ph.D.
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The effects of a heart attack are often permanent, as the heart tissue cannot regenerate, unlike some other tissues.
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This means that despite somebody surviving a heart attack, the damage done could cause health problems or death in the years following the event.
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Regenerating heart tissue to allow damaged heart tissue to be treated is a hot topic in research.
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Now researchers have discovered a mechanism that allows them to treat heart tissue in mice, before a heart attack, in a way that provides protection months later.
Although most people survive a heart attack
initially, the risk of death significantly increases over the following years.
In fact, 65% of people
who have a heart attack over the age of 65 die within eight years of the initial incident. This is at least partly because while a person may survive an initial heart attack, the heart attack itself, which leads to the heart tissue being deprived of oxygen and then dying, does not regenerate in adult humans.
In a recent animal study, researchers identified a mechanism that allowed them to treat heart tissue and make healthy mice’s hearts more resilient before a heart attack.
The study’s results appear in Nature Cardiovascular Research.
Heart attack and muscle death
Prof. James Leiper, Ph.D., Associate Medical Director at the British Heart Foundation and Professor of Molecular Medicine in the School of Cardiovascular and Metabolic Health at the University of Glasgow, U.K. told Medical News Today in an email:
“Most heart attacks are caused by coronary artery disease which can cause your coronary arteries to become narrowed. The narrowing is due to a gradual buildup of fatty deposits called atheroma. If a piece of atheroma breaks off, a blood clot forms around this to try and repair the damage to the artery wall. This clot can then block your coronary arteries causing the heart muscle to be starved of blood, oxygen, and vital nutrients, leading to heart muscle death.
The amount of damage to the heart muscle depends on the size of the area supplied by the blocked artery. As heart muscle is unable to regenerate it never fully repairs. Instead, scar tissue forms in place of healthy cardiac muscle.”
Cardiomyocytes are a type of cell in the heart that is responsible for the contraction of the muscle. This contraction of the muscle is essential for the heart to be able to squeeze blood around the body, in response to electrical signaling that maintains the heartbeat. When these cells are damaged in a heart attack, the heart loses some of its ability to squeeze blood around the body as effectively.
While cardiomyocytes are able to proliferate in human fetuses, this ability is lost in mature adult humans. It is believed this is partly due to an evolutionary trade-off that sees the ability of mature cardiomyocytes to proliferate decline with contractile strength. This means damage caused by events such as heart attacks can not be corrected.
Healing challenges after heart attack
The stages of maturation through which cardiomyocytes go from fetal to adult cells are the focus of much research. Because cardiomyocytes can not proliferate after the damage caused by a heart attack, research has been done on how cardiomyocytes can be dedifferentiated back a stage, to one where they are able to proliferate. Elucidating the mechanisms around this could provide information about how heart tissue damage could be reversed.
However, previous research into dedifferentiated cardiomyocytes has shown that deleterious and lethal effects of irreversible dedifferentiation occur. This is most likely due to the fact that dedifferentiated cells could become proliferative in a way that is similar to cancer.
It has been hoped that redifferentiation of cardiomyocytes back to the state they were in before differentiation, could avoid some of these complications. However, it has been unclear if the potential beneficial effects of previous differentiation to a more proliferative state would remain.
Treating the heart before an attack
Researchers in Dr. Eldad Tzahor’s lab in the Weizmann Institute of Science Molecular Cell Biology Department, previously identified
that when a particular protein ERBB2, coded for by the ERBB2 gene was over-expressed, dedifferentiation, occurred. However, the cardiomyocytes in this dedifferentiated, more proliferative state had a limited ability to contract. Researchers then observed that when overexpression was stopped, the cardiomyocytes underwent redifferentiation and went back to their original contractile ability, and cardiac performance improved.
In the lab’s latest research, led by Dr. Avraham Shakked, Ph.D., they sought to investigate the mechanism behind this gene and protein and the longevity of its effects. They showed that when a transgenic mouse that had its ERBB2 gene temporarily activated at 3 months old had a heart attack 5 months later, it recovered.
This demonstrated that redifferentiated cardiomyocytes maintained some of their proliferative, and therefore healing capacity.
This was the most exciting finding for the team, lead author Dr. Avraham Shakked told MNT in an interview:
“Perhaps the most exciting is the cardioprotective effect of this whole sequence of events that we weren’t really expecting to find or see at all, and actually that has the most potential impact at some point in the future.”
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Future research on cardiac regeneration
The next steps for the team would involve elucidating the mechanism further. “One of the things that we’ll do is we’ll actually try and look into the mechanism behind that protection. Because if you can isolate the causative agent with a causative effect, then you don’t necessarily have to undergo a [dedifferentiation and redifferentiation] DR cycle, which could be quite invasive, or quite dramatic.
“If you know exactly what it was then you could probably be a lot more precise in achieving the same result,” he said.
The team had several hypotheses about what could be behind this mechanism and wanted to test them one by one, he said. Seeing if the findings could be replicated in non-transgenic mice or larger mammals, such as pigs, would be necessary before considering clinical applications in humans, he explained.
Prof. Mauro Giacca, Professor of Cardiovascular Sciences at King’s College London told MNT in an email: “The issue of understanding whether cardiomyocytes return to a physiological, differentiated state after being pushed to proliferate is a key question for clinical cardiac regeneration, and the results obtained by the Tzahor group in their elegant model are quite comforting in this respect. What was less expected is the issue of “rejuvenation” of these cardiomyocytes, which however makes a lot of sense, as replication requires extensive rearrangement of the epigenetic landscape of cardiomyocytes. This is an added bonus to the cardiac regeneration!”
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By Hannah Flynn on March 20, 2023 — Fact checked by Jill Seladi-Schulman, Ph.D.
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Poor sleep can shorten a person's heart-healthy years, new study shows
New research suggests that poor sleep can reduce a person’s heart-healthy years. Image design by MNT; Photography by Mondadori Portfolio/Getty Images & Alfred Gescheidt/Getty Images.
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Poor sleep is associated with a shorter lifetime for heart health, according to a new study of over 300,000 people.
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The study suggests that people with sleep apnea are most at risk of poorer heart health in the future.
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In understanding how healthy a person’s sleep is, a range of factors should be considered, including fragmented sleep, overall sleep time, snoring, and other aspects of restorative rest.
A new study reports, for the first time, the effect of poor sleep on the longevity of a person’s cardiovascular health.
Researchers from the University of Sydney in Australia and the University of Southern Denmark analyzed the sleeping experiences and cardiovascular medical histories of 308,683 middle-aged adults.
The study found that sleep disorders are associated with a significant reduction in the number of years of cardiac, or heart, health a person experiences.
Included in the study were clinical sleep disorders such as insomnia and breathing-related disorders, as well as a range of other sleep-related issues, such as schedule/ chronotype
(sleep type) conflicts, snoring, and daytime sleepiness.
The two most common breathing-related sleep disorders considered in the study were central sleep apnea and obstructive sleep apnea.
The analysis revealed that breathing-related sleep disorders were linked to a shortening of a person’s heart-healthy lifespan by around 7 years.
The study appears in BMC Medicine
.
What the study found
For women, breathing-related sleep disorders were associated with a 7.32-year reduction in heart-healthy years, and 6.73 years for men.
People who slept poorly, according to the study’s definition, saw an average 2-year reduction in cardiac health.
The study explores the many types of sleep problems and their effect on heart health.
“Sleep is multidimensional and complex,” study co-author Prof. Emmanuel Stamatakis told Medical News Today.
“Our study suggests that it needs to be addressed holistically, and not to limit the discussion to, e.g., sleep duration only,” he noted.
The study’s authors hope it encourages cardiologists and other doctors to bring up the topic of sleep with patients, and work with them to resolve issues that may affect heart health in the long term.
The daily impact of poor sleep
Beyond its long-term health effects, poor sleep can impact people’s daily lives in many ways.
Being overtired increases the risk of accidents due to slower reaction times and lapses of attention, noted Dr. Jonathan Cedernaes, a sleep specialist from Uppsala University in Sweden, who was not involved in the study.
In addition, it may degrade a person’s daily physical performance, impair metabolic function, and promote inflammation, he added. Bad moods, irritability, and an inability to concentrate are all hallmarks of not getting enough sleep.
”We all suffer from poor sleep from time to time, but it’s when it becomes chronic that it may become an issue to worry about — that is when one should consider seeking professional help from healthcare providers,” said Dr. Cedernaes.
Poor sleep and long-term health
Prof. Stamatakis suggested that the especially negative association between breathing-related sleep disorders and cardiac health may have to do with common issues underlying both.
“Breathing-related sleep disorders are caused to a large extent by established cardiovascular risk factors such as obesity and physical inactivity,” he pointed out.
Sleep-disordered breathing can also worsen sleep all by itself, resulting in more fragmented, and thus less restorative, sleep, noted Dr. Cedernaes.
He added that poor sleep has also been linked to abnormal regulation of the cardiovascular system, including the heart and blood vessels, as well as increased inflammation, blood pressure dysregulation, and a disruption of the sympathetic nervous system.
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What the study did
In the current study, the participants’ sleeping histories were either self-reported or submitted by clinicians. The two types of data were analyzed separately.
In research, there are always concerns about the accuracy of self-reported data. In this case, people may, for example, be asked to assess snoring they themselves do not hear. Prof. Stamatakis said that, nonetheless, self-reported sleep data generally capture the related health risks fairly well.
However, he cautioned that “[b]ecause of compromised accuracy, they [doctors] are bound to underestimate the true health consequences of poor sleep.”
Clinically observed breathing-related disorders reported by general practitioners or hospital doctors are less susceptible to measurement errors.
“This higher measurement accuracy is perhaps one of the reasons why breathing-related sleep disorders appear to have [such] dramatic effects on life expectancy and compromised cardiovascular health.”
– Prof. Emmanuel Stamatakis
The issue with scoring sleep
The researchers assigned each individual a composite sleep score, ranking them as poor sleepers, intermediate sleepers, or healthy sleepers. Clinically diagnosed conditions — insomnia, sleep-related breathing disorders, and other sleep disorders — were considered separately.
Dr. Cedernaes applauded the use of multiple sleep questions in recording participants’ experiences, as it may make the capture of more forms of sleep disruption likely.
However, it is difficult to design a perfect sleep questionnaire, he pointed out. “For instance,” he said, “the questions don’t separate naps versus nighttime sleep, nor weekday versus weekend sleep.”
Dr. Cedernaes suggested that dividing existing inquiries into more specific subquestions may produce different results.
Emphasizing the importance of sleep
While this is the first study to specifically investigate a loss of healthy cardiovascular years due to sleep issues, its findings are supported by previous research, said Dr. Cedernaes. In addition, earlier studies have been backed up by well-controlled interventions.
Fortunately, it has also been shown that “extending sleep — or even taking a nap — can improve such parameters,” the researcher noted.
For people with sleep issues of any kind, the study underscores the value of partnering with one’s physician to identify solutions, especially if one is receiving cardiological care.
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By Robby Berman on March 14, 2023 — Fact checked by Catherine Carver, MPH
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Can a Mediterranean diet help keep heart disease, dementia, and cancer at bay?
For some time researchers have suggested that a Mediterranean diet — high in fresh fruit and vegetables, beans, nuts, whole grains, and fish — may help lower heart disease risk and increase life expectancy. An increasing amount of scientific evidence now backs up this notion. Recent studies have linked reduced rates of cardiovascular disease, dementia, and cancers with Mediterranean diets. Medical News Today looked at the evidence and spoke to experts about the science behind the benefits of this diet.
Several recent studies suggest the Mediterranean diet can help keep several diseases and chronic conditions at bay. Image credit: Cameron Whitman/Stocksy.
Over the years, many diets have been proposed for keeping healthy or reducing the risk of specific diseases, but few of them have stood up to rigorous scientific scrutiny.
One exception, however, appears to be the Mediterranean diet.
Increasingly, studies are showing that there are significant health benefits for people who follow this eating plan. Not only has research shown that it reduces cardiovascular disease, but it may also benefit cognition, decrease diabetes risk, reduce the risk of some cancers, and alleviate symptoms of multiple sclerosis.
What is the Mediterranean diet?
is an umbrella term referring to diets based on the historic eating habits of people who live around the Mediterranean Sea.
According to the American Heart Association
, which recommends this type of diet for cardiovascular health, its key features are:
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high intake of vegetables, fruits, whole grains, beans, and legumes
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low-fat or fat-free dairy products, fish, poultry, non-tropical vegetable oils, and nuts
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limited added sugars, sugary beverages, sodium, highly processed foods, refined carbohydrates, saturated fats, and fatty or processed meats.
The Harvard School of Public Health adds to these recommendations, emphasizing the importance of healthy fats — olive oil, avocados, nuts, and oily fish.
It advises that people should eat red meat only occasionally, but get their protein from fish or seafood at least twice a week and eat small quantities of poultry, eggs, and dairy most days.
Although water should be a person’s main drink, people may also drink one or two small glasses of red wine each day, as per the traditional Mediterranean diet.
Researchers add, however, that a healthy diet should also be paired up with some form of enjoyable physical activity every day.
Dr. Scott Kaiser, a geriatrician, and director of Geriatric Cognitive Health for the Pacific Neuroscience Institute at Providence Saint John’s Health Center in Santa Monica, CA, noted:
“Research supports the benefits of adopting healthy lifestyle habits and indicates the critical importance this can play in shaping our future individual and collective health. […] Start with including lots of fresh vegetables — especially green leafy vegetables — and then enjoy fresh fruits— like berries — and other antioxidant-rich foods, along with fish, olive oil, and other foods rich in brain-healthy omega-3s.”
Why Mediterranean diets are healthy
Mediterranean diets have long been associated with benefits to cardiovascular health. In the mid-20th century, the Seven Countries study showed that dietary patterns in the Mediterranean and in Japan in the 1960s were associated with low rates of coronary heart disease and all-cause mortality.
Since then, research has shown that this type of diet not only benefits cardiovascular health, but it also reduces the risk of many other health conditions.
And recently, evidence has been increasing for the wide-ranging health benefits of following a Mediterranean diet. But what makes Mediterranean diets so healthy, exactly?
“The Mediterranean diet is characterized by high fruit and vegetables, high fiber, high levels of ‘good fats,’ moderate intakes of fish and meat, low amounts of high processed foods and sugary treat foods,” noted Dr. Eamon Laird, a visiting research fellow at Trinity College, Dublin, in Ireland.
“These food components give high amounts of fiber, good fats, antioxidants, polyphenols, vitamins and minerals — choline, vitamin C, potassium, B-vitamins, vitamin D from fish, etc. — [and] proteins which give health benefits throughout a large number of organ and tissue systems,” he explained.
Mediterranean diet and CVD
Lots of research has investigated the effect of a Mediterranean diet on the risk for cardiovascular disease (CVD).
A meta-analysis of several studies published in March 2023, with a pooled sample of more than 700,000 female participants, has found that, by adhering closely to a Mediterranean diet, women reduced their risk of CVD by 24%, and their risk of death from any cause by 23%.
According to Dr. Laird, “[w]omen are also much more likely to stick with the diet compared to men, which could explain why we see more of the health benefits in women.”
The meta-analysis seems to confirm the findings of previous research. For example, in 2015, another meta-analysis
had found that the Mediterranean diet could be a major factor in preventing CVD.
And it was the complete diet, rather than any particular aspect, that seemed to have this effect, as Dr. Joanna Hodges, an assistant teaching professor of nutritional sciences at Pennsylvania State University, told MNT.
“[The study] concludes that no specific component of the Mediterranean diet has been shown to be as beneficial as the whole diet [in CVD prevention],” she told us.
Mediterranean diet and cognitive health
There is also increasing evidence that the diet may enhance cognitive function. A study published in March
2023 that used UK Biobank data has just reported that individuals with a higher adherence to a Mediterranean diet had up to 23% lower risk for dementia compared with those who had lower adherence to a Mediterranean diet.
The study, which used data from more than 60,000 people, concluded that the Mediterranean diet lowered dementia risk even in those with a genetic predisposition for dementia.
The authors conclude that adopting a diet high in healthy, plant-based foods may be a strategy for reducing dementia risk.
Another study, also published in March 2023, which looked at postmortem Alzheimer’s pathology, found that those who had followed a Mediterranean or MIND diet, particularly one rich in leafy greens, had a much lower beta-amyloid load.
is thought to be responsible for many of the symptoms of Alzheimer’s disease.
The diet may also be beneficial for people with multiple sclerosis (MS). A preliminary study to be presented at the American Academy of Neurology’s 75th Annual Meeting in April 2023, found that people with MS who followed a Mediterranean diet had a 20% lower risk of cognitive impairment than those who followed it the least.
Mediterranean diet and cancer
The diet has been found to both reduce the risk of some cancers and improve the efficacy of some cancer treatments.
found that high adherence to the Mediterranean diet was associated with a lower rate of several cancers, including breast, colorectal, and prostate cancers.
This study concluded that the antioxidant and anti-inflammatory properties of components of the diet “prevent and counteract DNA damages and slow down the development of various forms of cancer.”
For prostate cancer, recent research has shown that eating a diet high in colorful fruits and vegetables both reduces the risk of developing prostate cancer and speeds recovery
in those who undergo radiation therapy for the disease.
The studies, from South Australia, found that diets high in lycopene
and selenium
reduced the risk.
Tomatoes, melons, papayas, grapes, peaches, watermelons, and cranberries are rich in lycopene, and white meat, fish, shellfish, eggs, and nuts contain high concentrations of selenium. All of these are recommended in the Mediterranean diet.
And it is not only prostate cancer patients whose treatment may be more effective on a Mediterranean diet.
A recent study presented at UEG Week 2022 found that the diet was significantly associated with an improved response to immunotherapy drugs in people with advanced melanoma.
How it works
Although the exact mechanism by which the Mediterranean diet benefits health is unclear, there is increasing evidence that the diet can have five main effects
:
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lowering lipids
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protecting against oxidative stress, inflammation, and platelet aggregation
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modifying hormones and growth factors involved in cancer pathogenesis
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restricting specific amino acids
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influencing the gut microbiome to produce metabolites that benefit metabolic health.
Dr. Laird explained to MNT how some components of the diet benefit health:
“Omega-3 fatty acids, phytosterols, resveratrol
, vitamins, and polyphenols may contribute to lower levels of inflammation (CRP
), and may improve endothelial
function. By reducing levels of inflammation, improving blood flow, improving insulin sensitivity, and improving lipid metabolism, by default you are also reducing some of the major risk factors for CVD, cognitive decline, cancers, and diabetes.”
Studies have found that it is best to take in these nutrients in their natural form as part of a healthy diet, such as the Mediterranean diet.
Although they can be obtained through supplements, there may be side effects to taking excessive amounts.
Small changes will make a difference
The Mediterranean diet is just one of many diets that have health benefits. Others include the MIND, Nordic, and DASH diets.
“The common thread throughout all the [healthy] diets is a heavy influence of plant foods, which we see […] has numerous benefits in increasing dietary fiber, antioxidants, phytonutrients, vitamins, and minerals,” said Kate Cohen, a registered dietitian at the Ellison Clinic at Saint John’s, part of the Ellison Institute for Transformative Medicine and Providence Saint John’s Health Center in Santa Monica, CA.
So, key to any healthy diet is incorporating plenty of vegetables, whole grains, and healthy fats. Most importantly, any dietary changes made should be long-term and sustainable to give health benefits.
“Long term it [the Mediterranean diet] may be difficult to follow in its true form, particularly to those accustomed to processed food diets. A good approach would be to slowly integrate components into your current diet and to build slowly — again variety is the spice of life and we should have a varied and diverse diet and not rely solely on one dietary pattern to meet all our needs and requirements and tastes — food is to be enjoyed too!”
– Dr. Eamon Laird
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By Katharine Lang on March 18, 2023 — Fact checked by Ferdinand Lali, Ph.D.
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Why a 'keto-like' diet may be linked to heart attack and stroke
Could a high-fat, low-carb diet similar to keto diets affect cardiovascular health? Image credit: Alejandro Moreno de Carlos/Stocksy.
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Researchers investigated whether high-fat, low-carbohydrate, keto-like diets increase cardiovascular risk.
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Keto-like diets were linked to twice as many cardiovascular events as standard diets.
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Further research is needed to confirm the results.
The ketogenic or “keto” diet involves
consuming around 10% of daily calories from carbohydrates, 30% from protein, and 60% from fat. The diet triggers a process called “ketosis,” wherein the body derives energy from burning fats rather than carbohydrates.
Some studies
suggest that a keto diet can help with weight loss, make cancer cells more vulnerable to chemotherapy and radiation, and reduce blood sugar levels among those with diabetes.
Case studies, however, suggest that the keto diet may exacerbate or cause high cholesterol.
Further studies investigating how keto diets affect cardiovascular health could inform dietary options for individuals with different health profiles.
Recently, a study led by Dr. Iulia Iatan, attending physician-scientist at the Healthy Heart Program Prevention Clinic, St. Paul’s Hospital and University of British Columbia’s Centre for Heart Lung Innovation in Vancouver, Canada, assessed how low-carbohydrate, high-fat (LCHF) diets, similar to keto diets, may affect cardiovascular risk.
The research found that a LCHF diet almost doubled the risk of cardiovascular events when compared to a standard diet.
The study was presented at a conference held jointly by the American College of Cardiology and the World Heart Federation — the ACC Annual Scientific Session together with the World Congress of Cardiology.
What the study did
For the study, the researchers analyzed information collected by the UK Biobank for individuals with data on serum lipids, metabolomic markers, and dietary patterns.
All participants had recorded their diet in a 24-hour food survey. Among them, 305 met the criteria for an LCHF diet, defined as consuming less than 25% of daily calories from carbohydrates and more than 45% from fat.
The researchers matched these participants with 1,220 individuals who were considered to be on a “standard diet,” and made up the control group. Participants’ average age was 54 years, and they had a mean body mass index (BMI) of around 27 — which placed them in the “overweight” category
Participants also had their blood drawn to measure their cholesterol levels. The researchers followed the participants for an average of 11.8 years.
The researchers noted that the diet is “keto-like,” due to its higher percentage of carbohydrates and lower levels of fats than a strict ketogenic diet.
During the follow-up period, 9.8% of participants on an LCHF diet versus 4.3% of controls experienced a cardiovascular event, including blockage in arteries, a heart attack, or stroke.
Those on LCHF diets had significantly higher LDL cholesterol levels and apolipoprotein B (ApoB) — a protein indicator of cholesterol levels.
Low-carb, high-fat diets and cardio risk
“When people shift their caloric intake from carbs to fat, and especially if it is predominantly saturated fat such as from animal products, LDL cholesterol and ApoB will go up. This has been known for decades,” Dr. Liam R. Brunham, associate professor of medicine at The University of British Columbia, one of the study authors, told Medical News Today.
“What our study showed is that the effect is not uniform, but that there is a subgroup of people that will have severe hypercholesterolemia [abnormally high cholesterol levels] while on a LCHF diet. This is the group in whom the greatest increase in cardiovascular risk was observed,” he noted.
Dr. Dana Hunnes, assistant professor at UCLA Fielding School of Public Health, who was not involved in the study, told MNT that “[t]his type of diet is supposed to be used short-term, primarily in individuals who have seizure disorders or neurological disorders as ketones can pass through the blood-brain barrier.”
“A keto diet is high in saturated fats (typically), animal products, and may raise cholesterol levels and inflammation/ stress,” she explained.
“A low-carb, high-fat diet […] similarly tends to be high in animal products, saturated fats, and low in carbs and fiber. These properties can increase cholesterol levels and inflammation in the body, as well as potentially influence the microbiome and increase the risk for heart disease,” she added.
Keto concerns
MNT also spoke with Michelle Routhenstein, a heart health dietitian at Entirely Nourished, a virtual nutrition counseling and consulting private practice. She told us that the study confirms her own observations.
“This study reiterates what I see in my private practice, [as] many individuals come to see me after being on the keto diet for several months with very high LDL and apolipoprotein A levels, two important [factors] that help establish risk for atherosclerosis,” she noted.
“The keto diet can be very high in saturated fat and low in soluble fiber, which negatively impacts both of these values,” Routhenstein cautioned.
Study limitations
When asked about the study’s limitations, Dr. Brunham noted that the study shows correlation but not causation.
He added that those on the LCHF and standard diet differed in characteristics such as BMI, obesity, and diabetes status, potentially skewing the results.
“In other words, it could be that people in the UK Biobank who reported consuming an LCHF diet were at greater risk of heart disease not because of the diet but because the people that choose this diet were inherently higher risk. We would need other types of studies such as randomized trials to fully understand this,” he noted.
Dr. John P. Higgins, a sports cardiologist at McGovern Medical School at The University of Texas Health Science Center at Houston, not involved in the study, added that further limitations include that diet and cholesterol levels were captured at only one time point.
He also questioned whether standard diets were really “standard” or whether they were a more healthy group overall.
Research implications
“This type of study provides new insights to researchers and clinicians but should not be the basis for public policy,” cautioned Dr. Brunham.
“Given that there are still many unknowns in the field, a conservative implication would be that patients on a LCHF diet should monitor their lipid levels, and if they develop severe hypercholesterolemia should consult with a medical professional about managing their cardiovascular risk,” he added.
“I’ve been saying this for a while but, our bodies are not meant to live on ketones, and definitely not for any long periods of time,” noted Dr. Hunnes.
“These findings demonstrate that high intakes of animal products and fats seem to increase the likelihood or risk of a cardiac event; and this too, is something the science has agreed with for decades,” Dr. Hunnes added.
“The Mediterranean diet and Blue Zones diets are primarily [including] whole foods that are plant-based. We would be better served — as far as heart disease and other chronic conditions are concerned — to try and eat more like those who live in the Mediterranean or Blue Zones than a high-fat, high-protein, low-carb diet,” she concluded.
