For several decades, a leading theory on the cause of Alzheimer disease is that a toxic protein called beta amyloid builds up in certain parts of the brain, impairing function. If that’s true, the next questions are 1) why does the protein accumulate, and 2) what can be done to prevent it.
From ABC News:
Allegations that part of a key 2006 study of Alzheimer’s disease may have been fabricated have rocked the research community, calling into question the validity of the study’s influential results.
Science magazine said Thursday that it uncovered evidence that images in the much-cited study, published 16 years ago in the journal Nature, may have been doctored.
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More than $1 billion of government funding, through the National Institutes of Health, has been directed to amyloid-related Alzheimer’s research. While the investigation suggests that studies of Aβ*56 should be opened up to new scrutiny, experts said the entire theory shouldn’t be discredited.
Steve Parker, M.D.
PS: The Mediterranean diet is linked to lower risk of dementia.
Posted onApril 3, 2025|Comments Off on Specific Diets That Lower CRP Levels May Prevent Chronic Diseases
Olive oil is a prominent component of the Mediterranean diet
C-reactive protein (CRP) is a bloodstream marker of body-wide inflammation. A prominent theory is that if your CRP is too high, it causes chronic disease states like hypertension, dementia, and cardiovascular disease. A 2024 meta-analysis published in British Journal of Nutrition looked at the effects of various diets on CRP. The implication is that your odds of developing particular chronic diseases is lowered if you adopt a diet that lowers your CRP. Check the Abstract below to see how your diet stacks up:
Adopting a healthy dietary pattern may be an initial step in combating inflammation-related chronic diseases; however, a comprehensive synthesis evaluating current evidence is lacking. This umbrella review aimed to summarise the current evidence on the effects of dietary patterns on circulating C-reactive protein (CRP) levels in adults. We conducted an exhaustive search of the Pubmed, Scopus and Epistemonikos databases, spanning from their inception to November 2023, to identify systematic reviews and meta-analyses across all study designs. Subsequently, we employed a random-effects model to recompute the pooled mean difference. Methodological quality was assessed using the A Measurement Tool to Assess Systematic Reviews 2 (AMSTAR 2) checklist, and evidence certainty was categorised as non-significant, weak, suggestive, highly suggestive or convincing (PROSPERO: CRD42023484917). We included twenty-seven articles with thirty meta-analyses of seven dietary patterns, fifteen of which (50 %) exhibited high methodological quality. The summary effects of randomised controlled trials (RCT) found that the Mediterranean diet was the most effective in reducing circulating CRP levels, followed by Vegetarian/Vegan and Energy-restricted diets, though the evidence was of weak quality. In contrast, Intermittent Fasting, Ketogenic, Nordic and Paleolithic diets did not show an inverse correlation with circulating CRP levels. Some results from combined interventional and observational studies, as well as solely observational studies, also agreed with these findings. These dietary patterns show the potential in reducing CRP levels in adults, yet the lack of high-quality evidence suggests future studies may alter the summary estimates. Therefore, further well-conducted studies are warranted.
Posted onMarch 19, 2024|Comments Off on Should You Take a Vitamin D Supplement to Prevent Dementia?
Dr. John Campbell is “totally convinced” that high-dose vitamin D supplementation would prevent many cases of dementia, particularly Alzheimer dementia, which is 75% of all dementia cases. He takes 4,000 IU of vitamin D/day plus 100 mcg of vitamin K2. Unclear to me if that’s year-round or only in fall and winter. I assume it’s oral vitamin D3 (there are several types of vitamin D). Dr. Campbell didn’t say why he takes the K2. Click for a brief review of K2. In contrast to his vitamin D dose of 4,000 IU/day, U.K. health authorities recommend a tenth of that — 400 IU — in autumn and winter.
Make your own vitamin D with adequate sun exposure
Several observational studies link higher risk of dementia with blood levels of vitamin D that are deficient or insufficient. Blood levels of 25-hydroxy-vitamin D under 25 mg/ml are particularly linked to dementia. Dr. Campbell admits that it’s difficult to prove that adequate vitamin D supplementation would prevent Alzheimer dementia.
A Mediterranean diet of seafood, whole grains, nuts, fruit and vegetables could lower the risk of dementia by almost a quarter, according to a recent study.
Significantly the findings suggested that, even for individuals with a higher genetic predisposition to dementia, having a more Mediterranean-like diet reduced the likelihood of developing dementia.
The study which has been ongoing for the past two years, was led by Newcastle University in collaboration with colleagues from Queen’s University Belfast, University of Exeter, the University of East Anglia and the University of Edinburgh and has been published in the medical journal, BMC Medicine.
This was a large-scale project with analysis of data from over 60,000 older adults in the UK, which explored whether individuals who followed a Mediterranean-like diet had a lower risk of developing dementia than those who did not.
The research found that those with the highest level of adherence to a Mediterranean diet had a 23% reduced risk of developing dementia over a nine-year period than those with the lowest level of adherence.
Posted onJune 12, 2023|Comments Off on Is Alzheimer Dementia Caused by Excessive Fructose Consumption?
Colorado researchers theorize that fructose metabolism may be the driving force behind Alzheimer Disease pathology. Diets high in sugar and high glycemic index carbohydrates would exacerbate the problem. Salt may also play a role. Fructose is a simple sugar (a monosaccharide) typically found in fruit, honey, and some vegetables. Table sugar is sucrose, a combination of fructose with a glucose molecule. High-fructose corn syrup (HFCS) is added to many processed foods as a bulk-sweetener. From the article at linked above:
An ancient human foraging instinct, fueled by fructose production in the brain, may hold clues to the development and possible treatment of Alzheimer’s disease (AD), according to researchers at the University of Colorado Anschutz Medical Campus.
“We make the case that Alzheimer’s disease is driven by diet,” said the study’s lead author Richard Johnson, MD, professor at the University of Colorado School of Medicine specializing in renal disease and hypertension. The study co-authors include Maria Nagel, MD, research professor of neurology at the CU School of Medicine.
Steve Parker, M.D.
PS: The Mediterranean diet decreases risk of dementia.
Posted onNovember 10, 2022|Comments Off on Ultra-Processed Foods Associated With Impaired Cognition
Processed or ultra-processed?
An article earlier this year in the European Journal of Nutrition reported that high consumption of ultra-processed foods is linked to worse-than-average performance on one particular test of cognitive function in older U.S. adults (60+ years-old) who did not have chronic diseases such as diabetes or cardiovascular disease. The particular test was “Animal Fluency.” Never heard of it? Me either. Keep reading.
The study included 2,700 participants, average age 69. Participants were asked to recall what they ate in the prior 24 hours. Foods were “classified according to NOVA, a food classification based on the extent and purpose of industrial food processing, into four mutually exclusive groups: (1) unprocessed or minimally processed foods, (2) processed culinary ingredients, (3) processed foods, and (4) UPFs [ultra-processed foods].”
Ultra-processed foods? “…most foods described as “Frozen meals” or “Lunchables”, as well as some items described as consumed in “Restaurant fast food/pizza” or acquired at a “Vending machine” were classified as UPFs.” Furthermore, the authors write in the introduction that “UPFs, according to NOVA classification system, are industrial formulations of processed food substances (oils, fats, sugars, starch, and protein isolates) that contain little or no whole food and typically include flavourings, colourings, emulsifiers, and other cosmetic additives. UPFs are becoming dominant in diets globally and are replacing traditional diets based on unprocessed and minimally processed foods.
Of the entire study population at hand, UPFs were about half of all calories consumed but ranged from 30 to 70%.
“Cognitive performance was assessed using the Consortium to Establish a Registry for Alzheimer’s Disease (CERAD), Word Learning test, Animal Fluency test, and the Digit Symbol Substitution test (DSST).”
The Animal Fluency test “evaluates categorical verbal fluency (executive function).” “For the Animal Fluency test, the participant is requested to name as many animals as possible within a 60-s [60 seconds, I assume] time period. Each animal corresponds to 1 point and the result is presented as the total sum of points.”
Mr Ed, the fluent horse (You won’t get this if under 63)
The test subjects were given two other tests of cognitive function but the investigators found no differences in performance based on ultra-processed food consumption. Here are these other two tests:
The two parts of the CERAD Word Learning test consist of (1) three consecutive learning trials, where the participant is requested to recall a list of ten unrelated words immediately after their presentation. Each word corresponds to one point, and the result is presented as a total score across the three trials (range 0–30); and (2) a delayed word recall test, performed after the two other cognitive tests. The result ranges from 0 to 10. … For the DSST, the participant is presented a single sheet of paper where they are asked to match a list of nine symbols to numbers according to a key located on the top of the page. The task had 133 numbers and the participant had 2 min to complete it. The result is shown as the total number of correct matches. For all the tests, higher scores represent better cognitive function.
The authors conclude: “Consumption of UPF was associated with worse performance in Animal Fluency, a cognitive test that assesses language and executive function in older adults without pre-existing diseases such as CVD [cardiovascular disease] and diabetes, while no associations were observed for those with these conditions. While longitudinal studies are required to provide stronger evidence, these results suggest that decreasing UPF consumption may be a way to mitigate age-associated cognitive decline and reduce the risk of dementia.”
Posted onApril 30, 2022|Comments Off on Does MCT Oil Help in Alzeimer Disease?
One in four adults over 80 has Alzheimer Disease Photo by cottonbro on Pexels.com
The study at hand was very small, only 20 participants. So results may not be reproducible. The Canadian researchers’ main conclusion: “This is the longest duration MCT Alzheimer Disease study to date. Eighty percent had stabilization or improvement in cognition, and better response with 9‐month continual MCT oil.”
MCT stands for medium chain triglycerides, which apparently are derived from coconut and palm oil. The MCTs provide a source of energy for the brain – ketones – as a partial substitute for the brain’s usual energy source, glucose.
Study participants as expected were elderly and had mild to moderate Alzheimer Disease. Folks with diabetes were excluded from participation.
The article introduction has some interesting facts:
The brain is an obligate glucose metabolizer using 120 to 130 g/day of glucose. It uses 16% of the body’s total O2 consumption, despite representing only 2.0% to 2.3% of adult body weight. In conditions of low carbohydrate intake or fasting, the body uses ketones (acetoacetate and beta hydroxybutyrate [BHB]) as an alternative energy source to glucose. Ketones are normally generated in fasting states from beta‐oxidation of adipose stores to maintain cerebral function. In long‐term fasting, ketones can supply > 60% of the brain’s energy requirements, and are preferentially taken up by the brain over glucose. This occurs in cognitively normal younger and older adults, as well as in those with mild cognitive impairment (MCI) and AD.
Ketones can also be induced with a very low carbohydrate high fat (VLCHF) diet. Medium chain triglyceride (MCT) oil has the potential to produce a nutritional source of ketones for an alternative brain fuel to glucose, or by the consumption of MCT oil or esterases in freeze‐dried form. This is independent of the fasting state or carbohydrate intake. Long‐term compliance with fasting or VLCHF and LCHF diet regimes is challenging and requires strict medical supervision. Hence, the potential advantage of nutritional ketone sources (MCT) over these restrictive diets. Our recent study showed a clear dose‐dependent effect on ketone (BHB) generation with varying doses of MCT supplementation, and was found to be equivalent in young, elderly, and AD subjects.
In Alzheimer Disease (AD), the brain is unable to use glucose normally, causing hypofunction of 20% to 40% in key areas of the brain responsible for the symptoms in AD.
The MCT oil used was Bulletproof Brain Octane ® (NPN 80057199). Are other MCT oils just as good? Hell if I know. The goal dose was three tablespoons (15 ml) daily. My sense is that it was recommended as one tablespoon (15 ml) three times daily. The average consumption ended up as two tablespoons daily. Caregivers were in charge of dosing and they tended to forget or omit the lunchtime dose. Some study participants had limited dosing due to MCT side effects: abdominal pain, diarrhea, or vomiting.
Conclusion:
This study shows that participants taking MCT supplementation for 11 months continuously did better cognitively than their peers who had their 11 months of MCT interrupted by 4 months of placebo (olive) oil. Given that most patients should experience a drop in their cognitive scores over the 15 months, the fact that those on longer continuous MCT did not, could be a sample size error for the outcomes other than Montreal Cognitive Assessment, but it could also be that the difference in scores (showing stability) is valid.
In other words, MCT oil didn’t improve cognition, but stabilized it. I.e., it prevented the usual expected decline over time.
Question Is cataract extraction associated with reduced risk of developing dementia?
Findings In this cohort study assessing 3038 adults 65 years of age or older with cataract enrolled in the Adult Changes in Thought study, participants who underwent cataract extraction had lower risk of developing dementia than those who did not have cataract surgery after controlling for numerous additional risks. In comparison, risk of dementia did not differ between participants who did or did not undergo glaucoma surgery, which does not restore vision.
Meaning This study suggests that cataract extraction is associated with lower risk of developing dementia among older adults.
Importance Visual function is important for older adults. Interventions to preserve vision, such as cataract extraction, may modify dementia risk.
Details in the abstract:
Objective To determine whether cataract extraction is associated with reduced risk of dementia among older adults.
Design, Setting, and Participants This prospective, longitudinal cohort study analyzed data from the Adult Changes in Thought study, an ongoing, population-based cohort of randomly selected, cognitively normal members of Kaiser Permanente Washington. Study participants were 65 years of age or older and dementia free at enrollment and were followed up biennially until incident dementia (all-cause, Alzheimer disease, or Alzheimer disease and related dementia). Only participants who had a diagnosis of cataract or glaucoma before enrollment or during follow-up were included in the analyses (ie, a total of 3038 participants). Data used in the analyses were collected from 1994 through September 30, 2018, and all data were analyzed from April 6, 2019, to September 15, 2021.
Exposures The primary exposure of interest was cataract extraction. Data on diagnosis of cataract or glaucoma and exposure to surgery were extracted from electronic medical records. Extensive lists of dementia-related risk factors and health-related variables were obtained from study visit data and electronic medical records.
Main Outcomes and Measures The primary outcome was dementia as defined by Diagnostic and Statistical Manual of Mental Disorders (Fourth Edition) criteria. Multivariate Cox proportional hazards regression analyses were conducted with the primary outcome. To address potential healthy patient bias, weighted marginal structural models incorporating the probability of surgery were used and the association of dementia with glaucoma surgery, which does not restore vision, was evaluated.
Results In total, 3038 participants were included (mean [SD] age at first cataract diagnosis, 74.4 (6.2) years; 1800 women (59%) and 1238 men (41%); and 2752 (91%) self-reported White race). Based on 23 554 person-years of follow-up, cataract extraction was associated with significantly reduced risk (hazard ratio, 0.71; 95% CI, 0.62-0.83; P < .001) of dementia compared with participants without surgery after controlling for years of education, self-reported White race, and smoking history and stratifying by apolipoprotein E genotype, sex, and age group at cataract diagnosis. Similar results were obtained in marginal structural models after adjusting for an extensive list of potential confounders. Glaucoma surgery did not have a significant association with dementia risk (hazard ratio, 1.08; 95% CI, 0.75-1.56; P = .68). Similar results were found with the development of Alzheimer disease dementia.
Conclusions and Relevance This cohort study found that cataract extraction was significantly associated with lower risk of dementia development. If validated in future studies, cataract surgery may have clinical relevance in older adults at risk of developing dementia.
What else reduces risk of dementia? The Mediterranean Diet!
Viagra (one brand name for generic sildenafil) is used to treat erectile dysfunction and pulmonary hypertension. I bet that usage for ED is far more common than for pulmonary hypertension.
…the team analyzed insurance claims data from more than 7 million Americans. They found that the people (mostly men) who took sildenafil were 69% less likely to develop AD [Alzheimer’s Disease] over 6 years than those who did not take the drug. This association between sildenafil and AD held after adjusting for sex, age, and other diseases and conditions.
To understand how sildenafil might affect AD, the researchers grew neurons from stem cells derived from AD patients. Exposing the cells to sildenafil led to increased growth of neurites, which connect neurons to each other, and decreased tau phosphorylation, an early biomarker of AD.
Taken together, these results show an association between sildenafil use and reduced AD risk. But the researchers emphasize that they haven’t shown that sildenafil prevents or reverses AD.
These things usually don’t pan out, but one can hope. How often were these guys taking viagra? Once a month? Twice a week? To treat erectile dysfunction, sildenafil is typically taken as needed one hour before sexual activity. Typical dose for pulmonary hypertension is 20 mg by mouth three times a day, every day. Would this drug affect dementia in women? As they say, further studies are needed.
Advanced Mediterranean Diet 