10/23:  Macronutrients & Brain Health

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Brain HQ:  https://v4.brainhq.com/ 

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Presentation

From a student: Algal oil (click down arrow to read)

From  WebMD

Overview

Algal oil is an oil from marine algae that is rich in certain omega-3 fatty acids, including docosahexaenoic acid (DHA) and eicosapentaenoic acid (EPA). 

Certain algae species are grown in agriculture specifically to produce algal oil. It can be made from a variety of species, including Crypthecodinium, Nannochloropsis, Schizochytrium, Prototheca, and Ulkenia. The fatty acids in the oil might reduce swelling and help with brain function.

People use algal oil for preventing preterm birth. It is also used for improving thinking skills, physical performance, autism, ADHD, depression, and many other purposes, but there is no good scientific evidence to support these uses.

Don't confuse algal oil with specific types of algae, such as blue-green algae, brown algae, chlorella, or laminaria. Also, don't confuse algal oil with DHA or EPA from other sources such as fish oil, krill oil, or cod liver oil. These are not the same.

Uses & Effectiveness ?

Possibly Effective for

Preterm birth. In people who get less DHA from their diet, taking DHA-enriched algal oil by mouth during pregnancy seems to lower the risk of having a baby very early.

Possibly Ineffective for

Memory and thinking skills (cognitive function). Taking DHA-enriched algal oil by mouth doesn't seem to improve cognitive function or reading ability in most children.

Cystic fibrosis. Taking DHA-enriched algal oil by mouth doesn't seem to improve symptoms of cystic fibrosis.

Fractures. Taking algal oil by mouth doesn't seem to reduce the risk of fractures in older adults.

Physical performance in elderly adults. Taking algal oil by mouth doesn't seem to improve muscle strength in older adults.

There is interest in using algal oil for a number of other purposes, but there isn't enough reliable information to say whether it might be helpful.

Pregnancy and breast-feeding: Algal oil that is rich in DHA, an omega-3 fatty acid, is likely safe when taken by mouth when pregnant or breast-feeding. Algal oil is included in some prenatal vitamins and infant formulas as a source of DHA. If it is taken while pregnant or breast-feeding, DHA levels in the breast milk increase. Most experts recommended consuming 300 mg of DHA daily while pregnant and breast-feeding. This can be met by eating 8-12 ounces of seafood weekly during pregnancy, and 4-8 ounces weekly while breast-feeding. Those who are nutrient deficient or who do not eat fish may need to take a supplement such as algal oil. There isn't enough reliable information to know if algal oil rich in EPA, another type of omega-3 fatty acid, is safe to use when pregnant or breast-feeding. Stay on the safe side and avoid use.

Infants and children: Algal oil rich in DHA, an omega-3 fatty acid, is likely safe for infants and children. Algal oil is included as a source of DHA in some infant formula. It is generally recognized as safe for this use. Algal oil has also been used safely for up to 4 years in children 7 years and older in daily doses that provide 30 mg/kg of DHA. There isn't enough reliable information to know if algal oil rich in EPA, another type of omega-3 fatty acid, is safe to use in infants and children. Stay on the the safe side and avoid use.

Interactions ?

We currently have no information for ALGAL OIL Interactions.

Dosing

  Most algal oil products contain docosahexaenoic acid (DHA). Some products also contain eicosapentaenoic acid (EPA). Algal oil is included in many different types of products as a source of DHA, including infant formula and prenatal vitamins. Speak with a healthcare provider to find out what type of product and dose might be best for a specific condition.

Macronutrients and Brain Health

In this lesson, we start with “what is a calorie?” and then learn how to read a Nutrition Facts Panel. Then, we will take a deep dive into 3 macronutrients - carbohydrates, fats and protein. We will provide some general guidelines for some nutrients such as fiber, sugar and saturated fat. Finally, we will examine how each of the macronutrients are needed for optimal health and brain function. 

Question: Which macronutrient is the main source of fuel for the brain? (bonus: which type?)

What is a Calorie?


 A unit of energy, often used to express the nutritional value of foods, equivalent to the heat energy needed to raise the temperature of 1 gram of water by 1 °C

Macronutrients + Alcohol

Macronutrients are the nutrients we need in larger quantities that provide us with energy. The three macronutrients that contribute to overall calories include carbohydrates, fats and proteins. Carbohydrate and protein contain 4 calories per gram. Fat contains 9 calories per gram.

 

Alcohol is not considered a macronutrient because we do not need to consume it for bodily functions, but it does contain 7 calories per gram.

Nutrient Dense vs. Energy Dense

Instead of using the terms “healthy foods” and “unhealthy foods” let’s review the concepts of nutrient and energy-dense foods.  How we define health is different for each of us, and this is tied to our own unique values. Food neutrality is the understanding that no single food way of eating holds superior or moral value over another. 

 

Nutrient-dense: Amount of nutrients you get for the calories consumed; Foods that provide micronutrients such as vitamins, minerals and antioxidants, and have little added sugar, saturated fat and sodium.

 

Energy-dense: Measures the calorie content of foods per weight or volume.

Nutrient-dense foods[1]  can also be energy-dense. For example, nuts, seeds, some dairy products and ready-to-eat cereals can have high energy density (i.e., calories) and provide significant amounts of important nutrients.


https://www.eufic.org/en/understanding-science/article/what-is-nutrient-density 


Video:

What food neutrality?  This video explains the concept and why we view food the way we do.

Carbohydrates, Fats and Proteins

Before we dig deeper into carbohydrates, fats and proteins, let’s have a look at Nutrition Facts Label.

1. Check the Serving size first. All the numbers on this label are for a 2/3-cup serving.

2. This package has 8 servings. If you eat the whole thing, you are eating 8 times the amount of calories, carbs, fat, etc., shown on the label.


3. Total Carbohydrate shows you types of carbs in the food, including sugar and fiber.


4. Notice the dietary fiber, vitamins, and minerals (including Calcium and Vitamin D).


5. Be mindful of saturated fat, sodium, and added sugars. Avoid trans fat.



Carbohydrates

Simple Carbs

Simple carbs are a shorter molecular strand and break down in the body faster, which gives the body energy but for shorter amounts of time.

Complex Carbs

Complex carbs, a longer molecular strand, take more time to break down and give the body more sustainable, long lasting energy.

On the nutrition label, the term "total carbohydrate" includes all three types of carbohydrates. Below total carbohydrate is “dietary fiber” which reflects how much of the carbohydrate is fiber.


There are three main types of carbohydrate in food. There are:


● Starches (also known as complex carbohydrates)

● Fiber (also known as complex carbohydrates)

● Sugars (also known as simple carbohydrates)

Starches (complex carbohydrates)

Starches are carbohydrates found in foods like potatoes and grains, and they are important for providing energy and supporting overall health.

 
Foods high in starch include:


●     Starchy vegetables like peas, corn (technically a grain), lima beans and potatoes

●     Dried beans, lentils and peas such as pinto beans, kidney beans, black eyed peas and split peas

●     Grains like oats, barley, farro, buckwheat, barley, spelt, corn and rice.

The grain group can be broken down even further into whole grain or refined grain. A grain contains three parts:  bran, germ and endosperm.

Whole grains[1]  contain the entire grain – which is made up of bran, germ and endosperm.  The bran is the outer hard shell of the grain. It is the part of the grain that provides the most fiber and most of the B vitamins and minerals. The germ is the next layer and is packed with nutrients including essential fatty acids and vitamin E. The endosperm is the soft part in the center of the grain. It contains the starch. Whole grain means that the entire grain kernel is in the food. If you eat a whole grain food, it contains the bran, germ, and endosperm so you get all of the nutrients that whole grains have to offer.

Refined grains have been milled (ground into flour or meal) in a way that removes the bran and germ.  This gives them a finer texture and improves their shelf life but strips the grain of nutrients, including B-vitamins, iron and dietary fiber.  Examples include white and wheat flours, enriched breads, and white rice. Refined grains are often enriched, which means some of the B vitamins and iron are added back in after processing.

Remember that we can always add fiber and micronutrients into our food with other plant foods such as beans, lentils, veggies, fruit, nuts and seeds.


Infographic: https://wholegrainscouncil.org/ 

Fibers (complex carbohydrates)


Fiber comes from plant foods so there is no fiber in animal products such as milk, eggs, meat, poultry, and fish. Fiber is the indigestible part of plant foods, including fruits, vegetables, whole grains, nuts and legumes. When you consume fiber, most of it passes through the intestines and is not digested.

There are two types of fiber.  They are soluble fiber and insoluble fiber.

Soluble Fiber – dissolves in water, creates a gel, slows digestion (foods: nuts, seeds, legumes (lentils, beans, and peas, for example), oat cereals, fruit pectin (found in citrus fruits, apples, pears, apricots, and peaches), and some vegetables, such as carrots)

Insoluble Fiber – draws water into your stool, making it softer/easier to pass with less strain on bowel (foods: whole grains, wheat and corn bran, popcorn, seeds, nuts, broccoli, cabbage, root vegetables, onions, green leafy vegetables, fruit and vegetable skins)

 

According to the USDA’s Dietary Guidelines for Americans, adults need to try to eat 25 to 30 grams of fiber each day (that’s about 14g per 1000 calories eaten). Most Americans do not consume enough fiber in their diet so any increase in fiber in your diet can be beneficial. If you are thinking about adding more fiber to your dietary pattern, it may be beneficial to add incrementally so you don’t cause stomach upset.

Fiber offers some positive effects to your health.  They include: 

❖    Lowering blood glucose

❖    Lowering cholesterol levels

❖    Lowering blood pressure

❖    Increase in frequency of bowel movements (improved laxation)

❖    Increased mineral absorption in the intestinal tract

❖ Reduced energy intake (for example, due to the fiber promoting a feeling of fullness)

 

Fiber also supports a healthy gut. Fiber is the food source for the "good bacteria" in our gut. Having a "healthy gut" may correlate with our mental health, as 95% of serotonin is produced in the gut.

Video

We will be looking at the Gut-Brain connection in a future class but this short video explains the relationship between food and our brain health.

Sugars (Simple Carbohydrates)


You may get glucose in your body by eating carbohydrates such as grains, beans, fruits, starchy vegetables, and sugar. Your body breaks the carbohydrates down into glucose and then uses the glucose as fuel. Your liver stores the rest and releases it as needed. Glucose is the preferred fuel for our cells and preferred energy source for the brain as it supports the brain's overall functioning.

 

Brain functions such as thinking, memory, and learning are closely linked to glucose levels and how efficiently the brain uses this fuel source. If there isn’t enough glucose in the brain, communication between neurons breaks down because neurotransmitters (the brain’s chemical messengers) are not produced. In addition, hypoglycemia caused by low glucose levels in the blood can lead to loss of energy for brain function and is linked to poor attention and cognitive function.

Although the brain needs glucose, too much of this energy source can be harmful. High blood glucose levels can affect the brain’s functional connectivity, which links brain regions that share functional properties, and brain matter. It can cause the brain to atrophy or shrink. And it can lead to small-vessel disease, which restricts blood flow in the brain, causing cognitive difficulties and, if severe enough, spurring the development of  vascular dementia.

Type 2 diabetes is a condition that happens because the body can no longer regulate and use glucose as a fuel in an efficient way.  In type 2 diabetes, the pancreas does not produce enough insulin — a hormone that regulates the movement of glucose into the cells. Cells respond poorly to insulin which results in the uptake of less glucose (insulin resistance). This long-term condition results in too much glucose circulating in the blood. Type 2 diabetes can also accelerate brain aging, which may accelerate the progression of cognitive decline.

There are two main types of sugar:

●     naturally occurring sugars such as those in milk or fruit

●     added sugars such as those added during processing such as fruit canned in heavy syrup or sugar added to make a cookie

On the Nutrition Facts label, the number of sugar grams includes both added and natural sugars.  The recommendations are based on added sugar and not naturally occurring sugar.

The added sugar recommendations per the Dietary Guidelines for Americans found on the CDC website suggest that   Americans 2 years and older keep their intake of added sugars to less than 10% of their total daily calories. For example, in a 2,000 calorie diet, no more than 200 calories should come from added sugars (about 12 teaspoons).   Note: 4g of sugar = 1 teaspoon

The American Heart Association has lower recommendations for added sugar: They recommend that men should consume no more than 9 teaspoons (36 grams or 150 calories) of added sugar per day and that women consume no more than 6 teaspoons (25 grams or 100 calories) per day. 

There are many different names for added sugar. Examples of common names are table sugar, brown sugar, molasses, honey, beet sugar, cane sugar, confectioner's sugar, powdered sugar, raw sugar, turbinado, maple syrup, high-fructose corn syrup, agave nectar and sugar cane syrup.

You may also see table sugar listed by its chemical name, sucrose. Fruit sugar is also known as fructose and the sugar in milk is called lactose. You can recognize other sugars on labels because their chemical names also end in "-ose." For example glucose (also called dextrose), fructose (also called levulose), lactose and maltose.

Dietary Fat

Dietary fat is the fat that comes from food. Fats are important for how your body uses many vitamins.  We need fat to mobilize fat-soluble vitamins such as A, D, E, K and make these bioavailable (meaning, they can move around and be absorbed in our bodies).  The body breaks down dietary fats into parts called fatty acids (such as omega-3 fatty acids) that can enter the bloodstream. The body also can make fatty acids from the carbohydrates in food. The body uses fatty acids to make the fats that it needs.  Fats play a role in how all cells in the body are made and work.  Plus, fats carry flavor in the food we eat.

 

But all dietary fats are not the same. They have different effects on the body. Some dietary fats are essential. Some fats increase the risk for disease, and some help reduce the risk of disease.

 

Saturated fat tends to raise levels of cholesterol in the blood. Low-density lipoprotein (LDL) is sometimes referred to as "bad" cholesterol. High-density lipoprotein (HDL) is sometimes referred to as "good" cholesterol. Saturated fats raise the levels of both.

 

A high level of LDL cholesterol in the bloodstream increases the risk of heart and blood vessel disease which can also affect brain health. Less than 10% of calories a day should be from saturated fats (e.g., for a 2000 calorie level, less than 200 calories from saturated fats or less than 22g).The American Heart Association suggests a goal of 5% to 6% of daily calories from saturated fats.


A high level of LDL cholesterol in the blood can result in atherosclerosis [1] (a thickening or hardening of the arteries caused by a buildup of plaque in the inner lining of an artery). Atherosclerosis can affect most of the arteries in the body, including arteries in the heart, brain, arms, legs, pelvis, and kidneys. It has different names based on which arteries are affected. 

Vertebral artery disease is atherosclerosis in the arteries that supply blood to the back of the brain. Risk factors may include high cholesterol and triglyceride levels, high blood pressure, smoking, diabetes, obesity, and saturated fats. Atherosclerosis can cause a heart attack, stroke, aneurysm, or blood clot.

Vascular contributions to cognitive impairment and dementia (VCID) are a common cause of cognitive decline. While the cause of VCID is complex research suggests that there is a significant impact from atherosclerosis. Risk factors include hypercholesterolemia (high cholesterol) and hypertension (high blood pressure).


https://www.nhlbi.nih.gov/health/atherosclerosis

Trans fats raise your LDL cholesterol levels and lower your HDL cholesterol levels. Eating trans fats increases your risk of developing heart disease and stroke. It is also associated with a higher risk of developing type 2 diabetes.


Trans fats can be found in many industrially manufactured foods – including fried foods like doughnuts, and baked goods including cakes, pie crusts, biscuits, frozen pizza, cookies, crackers, and stick margarines and other spreads. If you see "partially hydrogenated oils" on the ingredient list, it’s your first clue there are trans fats in the product. You can determine the amount of trans fats in a particular packaged food by looking at the Nutrition Facts panel. However, products can be listed as “0 grams of trans fats” if they contain 0 grams to less than 0.5 grams of trans fat per serving.

Small amounts of trans fats occur naturally in some meat and dairy products, including beef, lamb and butterfat. There have not been sufficient studies to determine whether these naturally occurring trans fats have the same harmful effects on cholesterol levels as trans fats that have been industrially manufactured.


Dietary Omega-3 fatty acids have been a subject of research on brain health. (Chianese et al, 2018; Dighriri et al, 2022; Dyall 2015)  In clinical trials, it has been suggested that consumption of omega-3 improves learning, memory ability, cognitive well-being, and blood flow in the brain. Several studies highlight that the consumption of long chain omega-3 (DHA and EPA) rich food has potential neuroprotective effects through their anti-inflammatory activities within the brain. And these neuroprotective activities of long chain omega-3 are believed to be potent for protection and/or treatment of cognitive decline and dementia. Furthermore, research suggests that there is a positive association between omega-3 and cognitive performances in older adults and/or patients with neurodegenerative diseases such as Alzheimer’s disease. 

These observations led to a number of clinical trials aimed at assessing whether dietary supplementation with long chain omega 3 fatty acids, mainly EPA and DHA, can restore cognitive function in older adults, patients suffering of Alzheimer’s disease or at risks of cognitive decline, psychosis or mood disorders. Overall, the results are mixed. In particular, several trials reveal no improvement of cognitive decline in Alzheimer’s patients. Some clinical trials report an improvement in cognition in subjects with mild cognitive decline.

As we learned from the lesson on supplements, due to the mixed results on supplementation, researchers suggest that omega-3 fatty acids be obtained through food if possible. Fatty fish have the highest concentrations of DHA and EPA. Vegetarian sources of omega-3 include walnuts, algal oil, chia seeds, ground flaxseed and hemp seed. 

Protein

Proteins are made up of chemical 'building blocks' called amino acids. Your body uses amino acids to build and repair tissues, cells, muscles and bones and to make hormones and enzymes.  The enzymes are essential for many chemical reactions and the hemoglobin that carries oxygen in your blood. 

 

Protein is made from twenty-plus basic building blocks called amino acids. Because we don’t store amino acids, our bodies make them in two different ways: either from scratch, or by modifying others. Nine amino acids must come from the food we eat; they are histidine, isoleucine, lysine, methionine, phenylalanine, threonine, tryptophan, and valine and are known as the essential amino acids.  Animal proteins such as meat, poultry, fish, eggs and milk are complete proteins providing a source of all 9 essential amino acids and are considered to be high quality proteins.

Plant-based proteins carry fiber and other micronutrients (vitamins and minerals). Combining plant-based protein foods (e.g., grains/rice and beans or nuts and grains) will complete proteins but you don’t need to eat complete protein at every meal. The goal is to get a variety over the course of the day. On the right is a chart of plant sources with protein.  The foods highlighted in blue contain all 9 amino acids and are known as complete proteins.


Essential Amino Acid: Tryptophan
Tryptophan is an essential amino acid that cannot be produced by the human body and must be obtained through your diet. Tryptophan can be found in many protein-based foods and dietary proteins including meats, dairy, fruits, and seeds.

Tryptophan plays a role in the production of:

●     Serotonin; a mood stabilizer

● Melatonin; which helps regulate sleep patterns

● Niacin or vitamin B-3; converts food to energy at the cellular level

● Nicotinamide also known as vitamin B-3

 

*Nicotinamide acts similarly to niacin but has a different molecular structure.

Research has shown that tryptophan has been shown to have direct effects on sleep, producing an increase in rated subjective sleepiness, and decrease in total wakefulness. This improved quality of sleep is associated with an improvement in cognitive measures, improved morning alertness and brain measures of attention.

Serotonin synthesis occurs in the periphery within the gut neurons and centrally within the neurons in the brain stem. For central serotonin production to occur, tryptophan first needs to gain access to the central nervous system via the blood-brain barrier.  Lowered mood is one of the major symptoms of depression. The major therapeutic agents for treating depression are antidepressants, many of which are selective serotonin reuptake inhibitors or combined serotonin/noradrenaline reuptake inhibitors.

Tryptophan can be found in the following foods:

●     Milk

●     Canned Tuna

●     Turkey and Chicken

●     Oats

●     Cheese

●     Nuts and Seeds

●     Bread

●     Chocolate

●     Some Fruits such as bananas, apples, prunes


Non-essential Amino Acid: Tyrosine

Tyrosine is a nonessential amino acid the body makes from another amino acid called phenylalanine. It is an essential component for the production of several important brain chemicals called neurotransmitters, including epinephrine, norepinephrine, and dopamine. Neurotransmitters help nerve cells communicate and influence mood. Consuming tyrosine, the precursor of dopamine (DA) and norepinephrine (NE), may help maintain neurotransmitter function and cognitive performance.

Tyrosine is found in soy products, chicken, turkey, fish, peanuts, almonds, avocados, bananas, milk, cheese, yogurt, cottage cheese, lima beans, pumpkin seeds, and sesame seeds.

 Macronutrients and the Brain (summarized)

Summary of how these macronutrients impact brain health:

Glucose: Primary fuel source for the brain and supports overall brain functioning, including thinking, memory, and learning. Excessive glucose can lead to brain shrinkage and small-vessel disease, affecting cognitive abilities.  Limit glucose, especially simple carbohydrates. 

Fiber: Supports a healthy gut, crucial for mental health.  95% of serotonin, a mood-regulating neurotransmitter, is produced in the gut. Include natural fiber in your diet.

Saturated Fats: Can raise cholesterol levels, increasing the risk of heart and blood vessel diseases, which can subsequently impact brain health. Can increase the risk of arteriosclerosis which can lead to strokes, aneurysms, and blood clots.  Fats are important for brain health, but saturated fats may harm blood vessels.  Limit saturated fats.

Trans Fats: Raise LDL (bad) cholesterol and lower HDL (good) cholesterol. Consuming too many trans fats Increase the risk of heart disease, stroke, and type 2 diabetes, all of which can impact brain health.  Transfats are associated with negative brain health.  Limit for best brain health.

Omega-3 Fatty Acids: Improve learning, memory, and cognitive well-being as well as increase blood flow in the brain.  Also offers potential neuroprotective effects due to anti-inflammatory activities within the brain.  They may also protect against cognitive decline and dementia.  Foods with omega-3 fatty acids have been shown to be beneficial.  Eat more of these.

Tryptophan: Essential for producing serotonin (mood stabilizer), melatonin (regulates sleep), and certain B-vitamins.  The improved sleep quality from tryptophan is linked to enhanced cognitive measures and attention.  Serotonin produced by Tryptophan is important in mood stabilization.  Enjoy foods with tryptophan for mood and sleep.

Tyrosine: Vital for producing neurotransmitters like epinephrine, norepinephrine, and dopamine, which help nerve cells communicate and influence mood. Also, it may help maintain neurotransmitter function and cognitive performance.  Enjoy foods with tyrosine for nerve cell communication and mood, as well as neurotransmitters and cognitive performance.

In essence, the nutrients and conditions discussed play pivotal roles in brain health, either by directly supporting cognitive functions, influencing mood and sleep, or by impacting conditions that can have secondary effects on the brain. Proper intake and balance of these nutrients are crucial for maintaining optimal brain health and cognitive function. 

Summary

Macronutrients - carbohydrates, fats and protein - are needed in large amounts for optimal health and brain function.  Consume nutrient dense foods when possible

The general guideline is to attain a variety of foods within these three macronutrient categories, including sources of fiber, omega-3 fatty acids and plant-based proteins such as beans, lentils, nuts and seeds. This will help you consume essential micronutrients such as vitamins and minerals. 

Works Cited

USDA Dietary Guidelines for Americans. Retrieved from: https://www.dietaryguidelines.gov/resources/consumer-resources Accessed on October 16, 2023

 

American Heart Association: Whole Grains, Refined Grains, and Dietary Fiber, retrieved form https://www.heart.org/en/healthy-living/healthy-eating/eat-smart/nutrition-basics/whole-grains-refined-grains-and-dietary-fiber. Accessed on October 16, 2023

 

Mayo Clinic: Dietary fiber: Essential for a healthy diet. Retrieved from

https://www.mayoclinic.org/healthy-lifestyle/nutrition-and-healthy-eating/in-depth/fiber/art-20043983, Accessed on October 16, 2023

 

 

 

Oldways Whole Grain Council. Retrieved from https://wholegrainscouncil.org/ Accessed on October 16, 2023

American Diabetes Association: Types of Carbohydrates. Retrieved from

https://diabetes.org/healthy-living/recipes-nutrition/understanding-carbs/types-carbohydrates. Accessed on October 16, 2023

 

Harvard Medical School: Sugar and the Brain. Retrieved from https://hms.harvard.edu/news-events/publications-archive/brain/sugar-brain. Accessed on October 16, 2023

 

American Heart Association: Trans Fats. Retrieved from https://www.heart.org/en/healthy-living/healthy-eating/eat-smart/fats/trans-fat Accessed on October 16, 2023

WebMD: Top foods high in tryptophan. Retrieved from https://www.webmd.com/diet/foods-high-in-tryptophan accessed on October 16, 2023

 

Mount Sinai: Tyrosine. Retrieved from https://www.mountsinai.org/health-library/supplement/tyrosine Accessed on October 16, 2023

 

The European Food Information Council (EUFIC): What is Nutrient Density. Retrieved from https://www.eufic.org/en/understanding-science/article/what-is-nutrient-density. Accessed on October 16, 2023

Institute of Medicine (US) Committee on Military Nutrition Research. The Role of Protein and Amino Acids in Sustaining and Enhancing Performance. Washington (DC): National Academies Press (US); 1999. 14, Amino Acid and Protein Requirements: Cognitive Performance, Stress, and Brain Function. Available from: https://www.ncbi.nlm.nih.gov/books/NBK224629/

 

National Heart Lung and Blood Institute of the National Institutes of Health. What is Atherosclerosis? Retrieved from https://www.nhlbi.nih.gov/health/atherosclerosis. Accessed on October 16, 2023

 

National Institute of Neurological Disorders and Stroke: Focus On Vascular contributions to cognitive impairment and dementia (VCID). Retrieved from

https://www.ninds.nih.gov/current-research/focus-disorders/focus-alzheimers-disease-and-related-dementias/focus-vascular-contributions-cognitive-impairment-and-dementia-vcid. Accessed on October 16, 2023

 

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