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Dementia is the chronic or persistent disorder of the mental processes involving loss of memory, judgment, language, motors skills or other intellectual function caused by damage to or death of the brain’s nerve cells (neurons).

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It is estimated that in the U.S., approximately 14% of the elderly population has dementia.1 The most common cause of dementia is the Alzheimer’s type, characterized by neuron plaques and tangled neuron fibers, followed by vascular dementia, which is caused by arterial plaques caused by lower blood flow to the neurons. The signs of dementia vary and may come on slowly or quickly but typically are slow and start with memory loss. Symptoms of dementia may include:

  • paranoia
  • agitation
  • personality changes
  • difficulty communicating
  • difficulty remembering
  • difficulty with coordination
  • disorientation
  • inappropriate behavior
  • hallucinations

The cause of dementia depends on the type. The cause of Alzheimer’s type dementia is not fully known, but patterns of risk factors have been identified. Ongoing research has suggested that the following factors may be related:

  • obesity
  • insulin resistance
  • high cholesterol
  • high blood pressure
  • inflammation
  • nutritional deficiencies

The risks for vascular-type dementia are essentially the same. Since all these are modifiable factors, prevention is possible, so eating foods in order to optimally reduce these risk factors becomes the primary goal.

  1. Plassman BL, Langa KM, Fisher GG, et al. Prevalence of dementia in the United States: the aging, demographics, and memory study. Neuroepidemiology 2007, 29:125-132.

Action Plan


  • The Nutritarian eating style, high in micronutrients and healthy fats, supports brain function and may reduce the risk of developing dementia. Phytochemical-rich foods, such as greens, berries, and nuts are linked to better brain health, largely because carotenoids, flavonoids, cruciferous-derived isothiocyanates, and other phytochemicals have antioxidant, anti-inflammatory, and other effects that protect the brain. Oxidative stress and neuroinflammation are thought to contribute to neurodegenerative disorders, such as dementia.1-3
  • In particular, berries, nuts, and green, leafy vegetables are protective.2 Berries are rich flavonoids, which have a strong protective effect on the brain. Cocoa, citrus fruit, and onions are also among the list of foods high in flavonoids that may be beneficial for the brain.4 Nuts are rich in polyphenols and healthful fats.5,6


  • Dr. Fuhrman’s general supplement protocol for adults (see Vitamin Advisor for details) includes:
  • Additional notes:
    • Deficiencies or insufficiencies in vitamin D or vitamin B12 may contribute to dementia,7,8 so a Nutritarian eating style in conjunction with a supplement regimen that includes sufficient amounts of vitamin B12, vitamin D, and DHA and EPA (omega-3 fatty acids) is recommended. 
    • Sufficient intake of omega-3 fatty acids (DHA and EPA) is important for maintaining brain health and cognitive function with aging, and low blood DHA or low DHA intake is linked to dementia.9-11 Daily supplementation with algae-derived DHA and EPA is recommended for all healthy adults who do not eat fish frequently. 


  • Exercise plays an important role in maintaining brain health with aging.12 In people with mild cognitive impairment or dementia, exercise may help improve cognitive function.13,14 


Find additional help

ONLINE: All members of can search the Ask the Doctor archives for discussions on this topic. Platinum and Diamond members can connect with Dr. Fuhrman by posting questions in the forum. Not a member? Join now.

IN PERSON: Book a stay at Dr. Fuhrman’s Eat to Live Retreat in San Diego, California. With options ranging from one, two and three months (and sometimes longer) you will be under Dr. Fuhrman’s direct medical supervision as you hit the “reset” button on your health. For more information: (949) 432-6295 or [email protected]

EVENTS: Join Dr. Fuhrman for an online boot camp, detox or other event. During these immersive online events, you’ll attend zoom lectures, follow a special meal plan, and have access to a special, live Q&A session with Dr. Fuhrman. Learn more about events.

  1. Spencer JP. Flavonoids and brain health: multiple effects underpinned by common mechanisms. Genes Nutr 2009, 4:243-250. doi: 10.1007/s12263-009-0136-3

  2. Morris MC. Nutrition and risk of dementia: overview and methodological issues. Ann N Y Acad Sci 2016, 1367:31-37. doi: 10.1111/nyas.13047

  3. Grodzicki W, Dziendzikowska K. The Role of Selected Bioactive Compounds in the Prevention of Alzheimer's Disease. Antioxidants (Basel) 2020, 9. doi: 10.3390/antiox9030229

  4. Flanagan E, Muller M, Hornberger M, Vauzour D. Impact of Flavonoids on Cellular and Molecular Mechanisms Underlying Age-Related Cognitive Decline and Neurodegeneration. Curr Nutr Rep 2018, 7:49-57. doi: 10.1007/s13668-018-0226-1

  5. Poulose SM, Miller MG, Shukitt-Hale B. Role of walnuts in maintaining brain health with age. J Nutr 2014, 144:561S-566S. doi: 10.3945/jn.113.184838

  6. O'Brien J, Okereke O, Devore E, et al. Long-term intake of nuts in relation to cognitive function in older women. J Nutr Health Aging 2014, 18:496-502. doi: 10.1007/s12603-014-0014-6

  7. Schlogl M, Holick MF. Vitamin D and neurocognitive function. Clin Interv Aging 2014, 9:559-568. doi: 10.2147/CIA.S51785

  8. Moore E, Mander A, Ames D, et al. Cognitive impairment and vitamin B12: a review. Int Psychogeriatr 2012, 24:541-556. doi: 10.1017/S1041610211002511

  9. Hosseini M, Poljak A, Braidy N, et al. Blood fatty acids in Alzheimer's disease and mild cognitive impairment: A meta-analysis and systematic review. Ageing Res Rev 2020, 60:101043. doi: 10.1016/j.arr.2020.101043

  10. Cederholm T. Fish consumption and omega-3 fatty acid supplementation for prevention or treatment of cognitive decline, dementia or Alzheimer's disease in older adults - any news? Curr Opin Clin Nutr Metab Care 2017, 20:104-109. doi: 10.1097/MCO.0000000000000350

  11. Zhang Y, Chen J, Qiu J, et al. Intakes of fish and polyunsaturated fatty acids and mild-to-severe cognitive impairment risks: a dose-response meta-analysis of 21 cohort studies. Am J Clin Nutr 2016, 103:330-340. doi: 10.3945/ajcn.115.124081

  12. Lee MC, Byun K, Kim JS, et al. Trends in exercise neuroscience: raising demand for brain fitness. J Exerc Rehabil 2019, 15:176-179. doi: 10.12965/jer.1938046.023

  13. Zhou XL, Wang LN, Wang J, et al. Effects of exercise interventions for specific cognitive domains in old adults with mild cognitive impairment: A meta-analysis and subgroup analysis of randomized controlled trials. Medicine (Baltimore) 2020, 99:e20105. doi: 10.1097/MD.0000000000020105

  14. Jia RX, Liang JH, Xu Y, Wang YQ. Effects of physical activity and exercise on the cognitive function of patients with Alzheimer disease: a meta-analysis. BMC Geriatr 2019, 19:181. doi: 10.1186/s12877-019-1175-

Ask The Doctor

The following are sample questions from the Ask the Doctor Community Platinum and higher members can post their health questions directly to Dr. Fuhrman. (All members can browse questions and answers.)


Any ideas on what contributes to memory loss or what can help it? I seem to be forgetting a lot. I am a 51-year-old female. Any advice will be appreciated.


Not only do atherosclerosis, poor nutrient intake, and lack of exercise cause memory impairment, but exposure to toxins, especially mercury, plays a role, too. Addressing all these issues with a Nutritarian diet and appropriate supplementation can protect the brain from further damage. Low B12 and low DHA levels are associated with aging of the brain and memory loss, so that should be addressed as well.


I am a 53-year-old menopausal follower of a Nutritarian diet of 5 years. I find that my memory is really deteriorating, but I’m not sure if this is related to menopause. If so, will it improve? If not, what can I do about it?


If you are truly sticking to a Nutritarian diet and supplementing appropriately and still notice memory worsening, get an MMA test to see if more B12 would be indicated. B12 is a cofactor in the conversion of methylmalonic acid (MMA) to another compound. If there is insufficient B12 present, MMA will be elevated. It’s a more sensitive test for B12 deficiency. B12 is involved in several cellular processes that impact memory formation and retention.

DHA is essential for memory, so make sure you are including this daily. Also, exercise is associated with better memory.


I know that a Nutritarian diet can help to prevent many illnesses, such as heart disease, diabetes, and cancer. Does Alzheimer’s have a nutritional component? Would eating a diet rich in plant foods help to prevent the build-up of plaque and unwanted beta-amyloids in the brain, which are linked to Alzheimer’s? Also, have you had any success with overcoming or minimizing dementia with a Nutritarian diet?


That is correct. One terrific advantage of eating this way is avoiding those food additives in processed foods and the inflammatory effects of low-nutrient eating that creates plaque and dementia.

Dementia is a dietary-induced disease, but, by the time it appears, it is only partially improved by excellent nutrition and not reversible because it represents loss of brain cells (shrinkage and cell death) due to oxidative stress and decreased oxygenation.


My mother, who is now 80, has Alzheimer’s and started showing symptoms a few years ago. Her mother, one of her sisters, and a brother started showing symptoms in their late 70s as well. I am 51 and fearful that I may also get it in my 70s since it runs in my mother’s family (but not, thank goodness, in my father’s family—my dad is 81 and as sharp as ever). I read that B3 and B12 may prevent the onset of Alzheimer’s. I am now taking Osteo-Sun and Gentle Care. Would you recommend that I take a B complex vitamin and, if so, how much for each type of B? I know your Gentle Care has B1, B2, and B3 but should I be taking more of these, and should I also be taking B12? How about the DHA+EPA Purity—would that help as well?


There is much you can do to reduce your risk of Alzheimer’s disease. A plant-strong, nutrient dense eating style has been associated with reduced risk, even in those individuals with genetic predisposition. In other words, it is the high processed food, high animal product diet that causes Alzheimer’s. A diet of mostly nutrient-rich plants contains the micronutrients and hormone favorability to keep your brain free of disease until death. Yes, the omega-3 fatty acids DHA and EPA protect the brain as well. Lower levels throughout life are associated with brain shrinkage with aging, so add DHA-EPA Purity, .75 ml daily.


Thank you Doctors for changing my life. I feel confident that I will not develop the heart disease that has plagued my family for the last two generations.

Alzheimer’s disease is also an illness that has affected many of my relatives on the paternal side of my family. As a geriatric nurse, I am very acquainted with dementia. I understand how a Nutritarian diet can prevent the dementias caused by stroke but what is the scientific reasoning behind it preventing Alzheimer’s? Can

Alzheimer’s really be prevented by a Nutritarian diet? Even if I am already 58 and have been following a Nutritarian diet for only a few months? Will it reverse any growth of the plaques and tangles that may already be in the brain?


Yes, the studies on Alzheimer’s and diet link the same dietary causation as heart disease (and every other disease).

People with Alzheimer’s disease have reduced cerebral glucose metabolism, which is related to insulin resistance (abdominal obesity, high lipids, hypertension, glucose intolerance). With insulin resistance, tissues become resistant to the effects of insulin. High insulin levels prevent beta-amyloid (the plaques) from being degraded and cleared. High blood sugar and insulin levels are pro-inflammatory and have been associated with an increased risk of cognitive dysfunction and Alzheimer’s disease.

A plant based, high nutrient dense diet reverses insulin resistance and all of the abnormalities associated with it. So, eating this way for the rest of your life, along with exercise, will be your best defense against this disease. I think the diet probably can clear plaque but more research is needed.


I heard recently that saffron helps to slow the progression of Alzheimer’s. Do you feel this is accurate information? If it is accurate, is the supplement pill form or the actual spice better for the best effect? Thanks.


The few studies on saffron and dementia patients suggest that yes, it can help the symptoms somewhat and even similarly to other drugs on the market for dementia with no reported side effects, however, these studies are looking at small groups of people and we’ll need to see a larger scale study to see if the result can be repeated. It is thought that maybe saffron could even play a role in decreasing amyloid aggregation and deposition, but this hasn’t been confirmed. So, this is all interesting, and we certainly are watching for more studies to come out on the subject. Other studies that used only a little sprinkling of the spice in food daily showed improvements in depression, so I don’t think it matters if one gets it in capsule form or not, but the capsule would provide some consistency with the dose that you take. The doses used in the studies were about 30 mg daily, although we still don’t know if more is better or less might be enough for some to get a response.


I would be tremendously grateful to hear your perspective on recent news that suggests that copper consumption may be associated with Alzheimer’s disease. Here is a link to a recent CNN article on this topic:

Specifically, I would like to know how this may relate to a Nutritarian diet. For example:

  1. While the research cited is still preliminary, would it be prudent for those following a Nutritarian diet to eat moderate amounts of the nutrient dense foods that are especially high in copper–just as we are careful not to eat enormous amounts of greens that are high in oxalic acid?
  2.  If so, which common Nutritarian foods are especially high in copper and, therefore, wise to eat in moderation?

Many of our favorite Nutritarian recipes use liberal amounts of cashews. Before I began following the Nutritarian lifestyle, I never ate cashews. Now I eat them regularly–as well as more beans, mushrooms, and greens than ever before, all foods which, if I understand correctly, are high in copper. I am worried.

My mother and my grandmother began their struggles with Alzheimer’s in their early 70s, while my mother-in-law and her mother began in their late 60s. None of them smoked nor drank alcohol. They were all active and thin, and I can truly say that my mother and my grandmother almost never ate processed foods. I don’t know what to make of this.

I would be immensely grateful for any suggestions you may have and will continue to share the amazing benefits of the Nutritarian lifestyle with others.


Copper is an essential nutrient needed by the body. Like selenium and other nutrients, both too little and too much is harmful. The foods you mentioned are not high in copper, like animal products are. For example, you might eat 1000 calories of meat or liver easily, but you cannot eat 1000 calories of beans or mushrooms. A few ounces of cashew a day will also not overdose you with copper. I advise a variety of foods and a variety of seeds and nuts with a conscious effort to consume walnuts, flax, and chia as part of your nut and seed intake. Alzheimer’s is predominately caused by the same factors that cause heart disease and these factors are remediated by the totality of features of a Nutritarian diet.


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