The following article is republished with permission from the author. It was originally published in the Health Science Journal (winter 2020) by the National Health Association (NHA).
There has been a long, disappointing history of gender bias and disrespect for women in science, medicine, and the creative arts. From artists like Colette and Camille Claudel to the African-American mathematicians who gave our space program its initial jump start, the creativity of women has often been appropriated and obscured by men who have profited from their work. Even though Marie Curie, a woman, holds the distinguished honor of being one of only four people in history to have received two Nobel prizes in science, gender disparities persist. The incredible x-ray diffraction studies of the DNA molecule by the English chemist Dr. Rosalind Franklin were crucial to understanding the molecular structure of DNA when they were appropriated by Watson and Crick. And when Watson and Crick eventually basked in the fame and Nobel limelight for their discovery of DNA, she became a relatively invisible and unknown footnote in the history of science.
This gender bias has been particularly apparent in medical treatment and health care. For years, the excessive number of hysterectomies performed in the US has been an appalling attack on women, especially when more supportive nutrition/conservative health care options could potentially have resolved various female problems in a more life-affirming manner. Trust me, if castrations were done with the ease and nonchalance of hysterectomies, there would be an army of male, Paul Revere-like whistleblowers galloping through the streets of our country, with guns drawn, clutching their genitals and screaming, “The surgeons are coming!” Without a doubt, there would be a constitutional amendment ensuring the divine right of men to bear testicles. Unfortunately, when the founding fathers declared that all men are created equal, they meant all white men and certainly not women and men of color. So women continue to fight a long battle for equal rights and fair treatment in the workplace, boardrooms, and the medical arena.
The history of routine hormone replacement therapy (HRT) is another glaring example of female abuse, negative bias, and neglect. When conjugated estrogens derived from horse urine (Premarin) were put on the market in the early 1940s, it cornered the market on HRT and became the most prescribed drug in America. Unfortunately, women were so undervalued and neglected that there were no rigorous controlled studies to address the potential risks of this treatment. What was overlooked, and is certainly not shocking, was that reproductive steroid hormones derived from horses are not metabolized efficiently by the liver of human females. As a result, these estrogens linger longer in circulation, increasing the risk of stroke and cancers of the breast, ovaries, and uterus. This potential risk and abuse went on for 50 years before the rigorous double-blind Women’s Health Initiative Study was finally done between 1993–1998 and clearly showed that HRT did increase the risk of stroke and cancer of women’s reproductive organs. A shameful 50 years of risk and abuse in which “modern” medicine obliviously overlooked the health care needs of women.
Currently, we are seeing gender discrepancy in one of the most frightening and devastating conditions of modern times, Alzheimer’s Disease (AD), associated with severe memory loss and cognitive decline. AD is the most common form of dementia affecting people over 65, and approximately 200,000 Americans under age 60 live with early-onset Alzheimer’s, either in an asymptomatic preclinical phase or with minor cognitive deficits. AD affects almost 6 million people, is the sixth leading cause of death in the US, and in 2019 cost our nation close to 300 billion dollars. From 2000–2017, deaths from AD increased by 145% while death from heart disease only increased by 9%, and AD kills more people than breast and prostate cancer combined. But what really got my attention and intrigues me is that two-thirds of people with AD are women. And since the pathological and early cognitive changes of AD often occur before the age of 60, the fact that women live about five years longer does not account for the increased incidence in women. It begs the question, why is AD more prevalent in women?
To address that question, it is essential to understand the significant neurological, vascular, and metabolic changes associated with AD. And as we discuss the debilitating pathology of AD, please keep in mind that there is a constellation of risk factors and lifestyle choices, including a high saturated fat animal-based diet, obesity, smoking, alcohol consumption, high blood pressure, chronic stress, and sleep deprivation can affect the progression of this disease and the underlying pathological changes. The brain of people with AD typically shows two changes that eventually cause deterioration and death of neurons.
(1) Senile plaques formed from amyloid peptide produced by damaged brain cells.
(2) Neurofibrillary tangles formed by chemically modified protein (tau protein) within the internal architecture of brain cells.
In addition to these neurological changes, it is now widely recognized that AD is also a vascular disease associated with high cholesterol and an increase in atherosclerotic plaques that reduce blood supply to the brain. Both PET scans and electron microscopic analysis have shown that high cholesterol also promotes the formation of amyloid plaques and neurodegenerative brain changes.
There are also data to suggest that LDL cholesterol, the risky ”bad” form of cholesterol, can damage the vascular barrier that separates blood circulation from the brain (the blood–brain barrier), allowing cholesterol to access and accumulate in the brain and foster the devastating changes of AD. Cholesterol in the brain can also oxidize into a dangerous reactive free radical form promoting oxidative stress and brain damage. This makes it imperative to eliminate all meat and dairy foods providing saturated fat and cholesterol and eat a broad base of plant foods containing the greatest concentration of antioxidants that reduce oxidative stress.
Consistent with this vascular component, there are data that support the association of increased homocysteine with the cognitive pathology of AD. Meat, eggs, and dairy products have high levels of the amino acid methionine, which is metabolized to the vascular toxin homocysteine. B vitamins/folic acid can transform and reduce blood levels of homocysteine and decrease potential vascular damage and plaque formation in the heart and brain. Unfortunately, the typical meat-based diet has a dearth of veggies and therefore lacks the B vitamins to modify its high homocysteine content. A plant-based diet loaded with plant proteins, including greens, legumes, and grains, have much lower levels of methionine and a high B vitamin content that is ideal for reducing the vascular damage and plaque formation associated with AD. For these reasons, in addition to the routine monitoring of your cholesterol profile, I also recommend measuring blood levels of homocysteine for people over 50.
Metabolically, oxidative stress and insulin resistance also play a major role in promoting the underlying pathology of AD. Eating an animal-based diet high in saturated fat overloads liver and muscle cells with fat and interferes with insulin’s ability to promote the entry of sugar into these cells. As cells resist the normal healthy action of insulin, sugar cannot enter these cells and abnormally increases in the blood, ultimately being converted into fat and weight gain. The elevated blood sugar and decreased glucose metabolism, along with insulin resistance, provoke the body to overproduce insulin. Excessive insulin in the blood along with decreased glucose metabolism is found in the early asymptomatic preclinical phase of AD and promotes the beginning of amyloid plaques long before the actual outcome of cognitive changes and dementia. Keep in mind that AD is usually diagnosed in the mild to moderate dementia phase. However, with new imaging technologies, including PET scans and MRIs, early deposits of amyloid and amyloid plaque formation can now be seen in the preclinical phase before there are any noticeable cognitive symptoms.
Concerning women, brain imaging studies have demonstrated a link between estrogen decline and an increased risk of AD in women. Typically women entering the perimenopausal period, between the ages of 40–60 (when estrogen levels begin to change/decline before menopause), have demonstrated a decline in brain energy and an increase in Alzheimer’s plaques. Consistent with these data, women who have hysterectomies, especially earlier in life, demonstrate a higher incidence of AD. So even though AD may be triggered by a decline in estrogen there is very little research and almost no public recognition of this connection.
While menopause is typically associated with aging and the decline of reproductive function, it is the reduction of brain estrogens that are linked with the disturbing neurological symptoms of menopause, including hot flashes, disturbed sleep, depression, and memory decline. And while the loss of the neuroprotective effect of estrogen is not the cause of AD, it certainly is a trigger that warrants more attention. It is important to realize that just taking additional estrogen is not the solution because of the stroke and cancer risk associated with estrogen, both in animal-derived or bio-identical form, and also because there are no short- or long-term controlled studies showing that HRT actually eliminates the early or progressive pathological changes of AD. So much more work needs to be done (and is finally being done) to unravel the intricacies of the female connection to AD.
There is no effective medical treatment for end-stage AD. Yet there are numerous anecdotal reports surfacing every day about people in advanced states of cognitive decline reversing their dementia with a combination of supportive lifestyle factors. These reports typically espouse a whole food, plant-based diet containing dark berries, walnuts, and a panorama of deep greens, cruciferous and starchy vegetables as instrumental in their recovery. While these stories are promising and should not be overlooked, they certainly do not provide the evidence base of more rigorous controlled clinical trials. At least not yet. However, they do hint at the remarkable plasticity and recovery of the brain, even in advanced stages of degeneration.
But the great, hopeful news for all women and men is that because of the known risk factors, and the long latent period between the formation of the plaques and tangles of AD and the outcome of severe cognitive decline/memory loss, early and ongoing lifestyle prevention strategies may dramatically reduce the severity of AD. While several small studies looking at short-term, single lifestyle prevention factors have been disappointing, the large Finger study from Finland, which targeted a combination of several important lifestyle behaviors and vascular risk factors simultaneously, demonstrated great promise and hope. In this study, between 2012–2014, 1,260 people aged 60–77 participated in a multi-domain approach including a diet combining whole plant foods with small amount of animal products, an activity program that included both aerobic (walking) and resistance weight training, cognitive intellectual activity/training, social activities and monitoring and management of metabolic and vascular risk factors. This landmark clinical trial showed significant improvement in all cognitive functions, including executive function (ability to manage and regulate ourselves and set and achieve goals), memory, and psychomotor speed, demonstrating that it is possible to prevent cognitive decline with a broad-based lifestyle approach.
Our attention needs to focus on prevention, and these data provide a remarkable picture of hope. It has become apparent that a whole food, plant-based diet provides the most important foundation for the necessary lifestyle modifications. A plant-based diet has more than 50 times the antioxidant potential than any other eating plan on planet Earth and is the most successful way to eliminate the oxidative stress associated with AD.
Eliminating the saturated fat and cholesterol found in meat and dairy products is the most effective way to reduce both amyloid and atherosclerotic plaques associated with AD. And this plant-based, low-fat approach is mandatory for healing the problems of insulin resistance and compromised glucose metabolism that promote the cellular changes of AD. Correcting these metabolic conditions and promoting an effective routine of consistent physical/intellectual activity, stress management, sleep, and social interaction while eliminating drugs, alcohol, and nicotine is essential. This lifestyle approach is beneficial for all people at any stage of AD progression, but it is especially important for women during the transition to perimenopause and menopause when the brain is most potentially vulnerable due to estrogen decline.
Never forget that AD is not an inevitable outcome of aging and longevity. Never underestimate the power of your personal, constructive lifestyle choices. And never underestimate the incredible power of a whole plant-exclusive diet for promoting your optimal health span in general and preventing devastating conditions like AD in particular. The choice is yours.
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