How Too Much Cholesterol Can Contribute to Alzheimer’s Disease

Millions suffer from Alzheimer’s disease, and the available and foreseeable treatments are disappointing at best. Given the absence of disease-modifying treatments, there has been growing interest in effective strategies for the prevention of the disease in the first place. Even if we were able to just delay the onset by as little as 1 year, we could potentially prevent more than 9 million cases over the next 40 years. Once cognitive functions are lost in Alzheimer’s disease patients, they may be lost forever. Consequently, prevention, rather than a cure for Alzheimer’s disease appears to be a more realistic strategy to offset the catastrophic impact of this dementia.

As I discuss in my video Cholesterol & Alzheimer’s Disease “[c]onsiderable evidence now indicates that Alzheimer’s disease (AD) is primarily a vascular disorder,” based on a number of lines of evidence that point toward impaired circulation of blood to the brain. Vascular risk factors, such as high cholesterol, can be thought of as a ticking time bomb to Alzheimer’s disease. What’s bad for the heart may be bad for the mind.

Traditionally, there have been two competing theories for the cause of Alzheimer’s: the amyloid cascade model, which implicates the buildup of amyloid plaques within the brain, and the vascular model, which argues that it is the lack of adequate blood flow to the brain due to atherosclerosis. We now realize they are not mutually exclusive and that arterial disease can set up a vicious cycle in which atherosclerotic plaques in the arteries may contribute to Alzheimer’s plaques in the brain.

Although cholesterol has been portrayed as “tantamount to poison,” it is an essential structural component of all of our cells, and that’s why our body makes it. But, if there’s too much, it can become a major factor contributing to various diseases, including coronary heart disease, stroke, and neurodegenerative diseases like Alzheimer’s. Too much cholesterol in our blood is universally recognizedto be a risk factor for the development Alzheimer’s disease, and cholesterol may play an active role in the progression of Alzheimer’s as well.

Autopsy studies have found that Alzheimer’s brains have significantly more cholesterol than normal brains, and it specifically appears to accumulate in the Alzheimer brain plaques. We used to think the pool of cholesterol in the brain was separate from the pool we had in our blood, but there is now growing evidence to the contrary. For example, low-density (LDL) cholesterol, the so-called bad cholesterol, may be able to cross the blood–brain barrier into the brain. So, a high-fat diet may not only increase cholesterol levels in the blood, but also the influx of cholesterol into the central nervous system.

In addition, having high cholesterol may even damage the blood-brain barrier itself, and allow for even more cholesterol to flow into the brain, providing the missing link between high cholesterol and Alzheimer’s. “Individuals with higher cholesterol levels at midlife have a higher risk of developing[Alzheimer’s disease].” Cholesterol over 250 could potentially triple the odds of Alzheimer’s.

We now have high-tech PET scanning of the brain that can directly correlate the amount of bad LDL cholesterol in our blood with the amount of amyloid buildup in our brains. You can even do it right in a petri dish. Adding cholesterol makesbrain cells churn out more of the amyloid that makes up Alzheimer plaques, whereas removing cholesterol can decrease the levels of amyloid released from cells.

Amyloid degradation is also less efficient in a high cholesterol environment. Cholesterol can then help seed the clumping of the amyloid. Using an electron microscope, researchers can see the clustering of amyloid fibers on and around little microcrystals of cholesterol.

Once in the brain, cholesterol can also undergo auto-oxidation, causing the formation of highly toxic free radicals. So, having high cholesterol levels in the blood is thought to increase the risk of dementia, not only by inducing atherosclerosis and impairing blood flow, but also by potentially directly affecting neurodegeneration within the brain. In conclusion, excess dietary cholesterol could, in principle, contribute to the development of Alzheimer’s disease, and the evidence linking high cholesterol to Alzheimer’s appears to be steadily mounting.

Some of this work was paid for by drug companies hoping to capitalize on Alzheimer’s with cholesterol-lowering statin drugs. This is ironic, since statins themselves can causecognitive impairment. Though rare, statin side effects may “include short- and long-term memory loss, behavioral changes, impaired concentration and attention, paranoia, and anxiety,” as early as five days after starting the drugs, but sometimes even months later, though folks should recover within a month of stopping the drugs.

A better strategy may be to changethe lifestyle factors that lead to the high cholesterol in the first place—in particular, reducing saturated fat in the diet. It’s not enough for us to just tell our individual patients, though. “Systematic implementation of educational campaigns promoting radical changes in cultural and societal values” may be necessary to adopt Alzheimer’s-defeating strategies by patients in a broader sense, and “such actions may provide potentially huge dividends by preventing both cardiovascular disease and dementia”—two of our leading causes of death.

Source: nutritionfacts.org

Who’s Right in the Salt Debate?

For decades, a sometimes furious battle has raged among scientists over the extent to which elevated salt consumption contributes to death, with one camp calling it a “public health hazard that requires vigorous attack” and another claiming the risks of dietary salt excess are exaggerated, even to the point of calling sodium reduction “the largest delusion in the history of preventive medicine.” The other side calls this denialism ethically irresponsible, especially when millions of lives are at stake every year.

To describe two sides of the debate may be falling into the trap of false equivalency, though. As the superhero-sounding “World Hypertension League” points out, there is strong scientific consensus that reducing salt saves lives, and—like the climate change debate—most authorities are on one side. On the other? Only the affected industry, their paid consultants, and a few dissenting scientists.

As I discuss in Sprinkling Doubt: Taking Sodium Skeptics with a Pinch of Salt, nearly all government appointed bodies and nutrition experts who have considered the evidence have recommended we collectively cut our salt intake about in half—a reduction described as extreme by those defending the industry. After all, just a small fraction of Americans actually get their sodium intake that low. Therefore, the salt skeptics say, the human experience for very low levels of sodium consumption is “extremely sparse.”

Extremely sparse? The reality is the exact opposite. The human experience is living for millions of years without Cheetos or a salt shaker in sight. We evolved to be salt-conserving machines, and when we’re plunked down into snack food and KFC country, we develop high blood pressure. But in the few remaining populations that don’t eat salt and only consume the small amounts of sodium found in natural foods like we had for millions of years, our leading killer risk factor, hypertension, is practically non-existent. When you take people with out-of-control hypertension and bring them back down to the sodium levels we were designed to eat, the ravages of the disease can even be reversed (see my video Drugs & the Demise of the Rice Diet). So, why is there still a debate?                    

If salt hidden in food kills millions of people around the world, why are efforts to cut dietary salt being met with such fierce resistance? Salt is big business for the processed food and meat industry. So, according to the head of the World Health Organization’s Collaborating Center on Nutrition, we get the familiar story. Just like the tobacco industry spent decades trying to manufacture doubt and confuse the public, the salt industry does the same, but the controversy is fake. The evidence for salt reduction is clear and consistent. Most of the “contradictory research” comes from scientists linked to the salt industry. However, it takes skill to spot the subterfuge because the industry is smart enough to stay behind the scenes, covertly paying for studies designed to downplay the risks. All they have to do is manufacture just enough doubt to keep the so-called controversy alive.

The likes of the World Hypertension League have been described as a “mere pop-gun against the weapons-grade firepower of salt-encrusted industries” who look disdainfully at the “do-gooder health associations…who erect roadblocks on the path to profits.” Lest we forget, notes an editorial in the Journal of the Canadian Medical Association, high blood pressure is big business for the drug industry, too, whose blood pressure billions might be threatened should we cut back on salt. If we went sodium-free and eliminated the scourge of hypertension, not only would Big Pharma suffer, what about doctors? The number-one diagnosis adults see doctors with is high blood pressure, at nearly 40 million doctor visits a year, so maybe even the BMW industry might be benefiting from keeping the salt debate alive.

   Written By Michael Greger M.D.

UN Environment and WHO agree to major collaboration on environmental health risks

10 JANUARY 2018 | NAIROBI - 
UN Environment and WHO have agreed a new, wide-ranging collaboration to accelerate action to curb environmental health risks that cause an estimated 12.6 million deaths a year.

In Nairobi, Mr Erik Solheim, head of UN Environment, and Dr Tedros Adhanom Ghebreyesus, Director-General of WHO, signed an agreement to step up joint actions to combat air pollution, climate change and antimicrobial resistance, as well as improve coordination on waste and chemicals management, water quality, and food and nutrition issues. The collaboration also includes joint management of the BreatheLife advocacy campaign to reduce air pollution for multiple climate, environment and health benefits.

This represents the most significant formal agreement on joint action across the spectrum of environment and health issues in over 15 years.

"There is an urgent need for our two agencies to work more closely together to address the critical threats to environmental sustainability and climate – which are the foundations for life on this planet. This new agreement recognizes that sober reality," said UN Environment’s Solheim.

"Our health is directly related to the health of the environment we live in. Together, air, water and chemical hazards kill more than 12.6 million people a year. This must not continue," said WHO’s Tedros.

He added: "Most of these deaths occur in developing countries in Asia, Africa and Latin America where environmental pollution takes its biggest health toll."

The new collaboration creates a more systematic framework for joint research, development of tools and guidance, capacity building, monitoring of Sustainable Development Goals, global and regional partnerships, and support to regional health and environment fora.

The two agencies will develop a joint work programme and hold an annual high-level meeting to evaluate progress and make recommendations for continued collaboration.

The WHO-UN Environment collaboration follows a Ministerial Declaration on Health, Environment and Climate Change calling for the creation of a global "Health, Environment and Climate Change" Coalition, at the United Nations Framework Convention on Climate Change (UNFCCC) COP 22 in Marrakesh, Morocco in 2016.

Just last month, under the overarching topic "Towards a Pollution-Free Planet", the United Nations Environment Assembly (UNEA), which convenes environment ministers worldwide, adopted a resolution on Environment and Health, called for expanded partnerships with relevant UN agencies and partners, and for an implementation plan to tackle pollution.