Researchers are exploring the correlation between sugar and depression, and have theorized that a protein called BDNF may be the link. BDNF plays an important part in the maintenance, growth and differentiation of nerve cells in the brain.

Sugar suppress the activity of BDNF, which is typically already low in people who have depression. Increasing your intake of protein can help control your sweet tooth and stabilize blood sugar. Protein bars, for instance, can be an effective snacking strategy to keep you satisfied between meals, however, pay attention to the sugar content in protein bars , as some protein bars can contain as much added sugar as a cookie.

Protein, as a macronutrient, includes foods that are typically high in iron. Low iron can cause anemia, and is the most common nutritional deficiency in the world. Anemia can leave you feeling fatigued, irritable and disengaged.

You may feel unmotivated or unable to sustain physical activity for long periods of time, which can contribute to feelings of depression. Treating anemia will improve your mood and make it easier to function.

Nuts are a great brain-healthy snack. They contain fiber, fats, and antioxidants. The MIND diet recommends that you eat nuts five times weekly. Berries also provide protective benefits, especially blueberries. Consume a mixture of berries at least twice weekly.

Consume more high-protein, fiber-rich beans. You should also consume whole grains. The recommended amount is at least three servings daily.

This may include brown rice, whole oats, whole rye, barley, buckwheat, quinoa, and bulgur. Fish also protects brain function, which is why you should consume wild-caught, fatty fish once a week.

Poultry is also part of this brain-healthy plan. The MIND diet recommends that you consume two or more servings a week. Also, limit your intake of red meat to no more than four servings weekly. In contrast, avoid margarine and limit your intake of butter.

Instead, consume a quality source of olive oil. You should also reduce your intake of cheese to no more than once a week and significantly reduce your intake of sugar. When proteins are broken down or digested, amino acids are left behind.

Amino acids are used to make protein to perform essential body functions. A complete protein or whole protein is a source of protein that contains an adequate proportion of all of the essential amino acids required for our dietary needs.

There are eight essential amino acids that are the components of the proteins mandatory in a healthy diet:. The body does not store essential amino acids. If we do not get all eight essential amino acids together in the same meal the body will just break them down for energy instead of building proteins for repair and growth.

Getting all eight together is most easily accomplished by eating animal meat, fish and animal products eggs, milk, cheese. Martha Lindsay MS, CNE, Certified GAPS practitioner, uses the following formula to determine how much complete protein you require each day:.

The resulting number gives you the number of grams of protein you need each day for proper overall body health maintenance and brain optimization. Lindsay makes it clear that in some cases, a person may need more protein. These situations include illness, recovering from injury, pregnancy , and body building.

Some suggested sources of protein are listed below with the grams of protein contained in a serving size. With the right diet, you can increase healing, combat illness and disease, improve mental clarity, fight fatigue, boost your memory , reduce inflammation and so much more.

Nourish your body and boost your brain with the right amount of complete protein to feel your best and optimize your health. Diane Roberts Stoler, Ed.

Short cycles of a low-calorie diet that MIND and Mediterranean Diets Associated With Later Onset of Parkinson's Disease. While researchers have long known of neuroprotective effects How Protein Protects Against Fatty Liver. A high-protein, calorie-reduced diet can cause the harmful liver Long-Term Benefits of a Low-Fat Diet.

The findings found a low-fat diet commensurate with an increase in fruit, vegetable and grain servings reduced death Print Email Share. Trending Topics. Immune System. Breast Cancer. Child Development. Healthy Aging. Smart Earrings Can Monitor a Person's Temperature. Researchers 3D-Print Functional Human Brain Tissue.

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Am J Epidemiol. Yuan C, Cao Y, Ascherio A, Okereke OI, Zong G, Grodstein F, et al. Long-term diet quality and its change in relation to late-life subjective cognitive decline. Keywords: dietary protein, animal protein, plant protein, cognitive decline, protein intake.

Citation: Gao R, Yang Z, Yan W, Du W, Zhou Y and Zhu F Protein intake from different sources and cognitive decline over 9 years in community-dwelling older adults.

Public Health Received: 10 August ; Accepted: 29 September ; Published: 14 October Copyright © Gao, Yang, Yan, Du, Zhou and Zhu. This is an open-access article distributed under the terms of the Creative Commons Attribution License CC BY. The use, distribution or reproduction in other forums is permitted, provided the original author s and the copyright owner s are credited and that the original publication in this journal is cited, in accordance with accepted academic practice.

No use, distribution or reproduction is permitted which does not comply with these terms. Disclaimer: All claims expressed in this article are solely those of the authors and do not necessarily represent those of their affiliated organizations, or those of the publisher, the editors and the reviewers.

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Sections Sections. About journal About journal. Article types Author guidelines Editor guidelines Publishing fees Submission checklist Contact editorial office. ORIGINAL RESEARCH article Front. RELATED — The Vegan Diet and Lifestyle: Benefits, Risks and Meal Plans. Plant proteins come in different forms, each containing important nutrients.

Below are some sources of dietary proteins from plant products. For those following a vegan diet, eating a range of plant-based proteins is important. Mixing sources of proteins means that vegans are able to receive all the essential amino acids. Nearly all vegetables, beans, nuts and grains contain protein, so it is relatively easy to meet daily protein requirements.

All animal products contain proteins but amounts vary depending on the type of animal, age and cut of meat. There is no definitive answer to how much protein a person needs to consume.

The amount of protein our body needs depends on our individual activity level, weight, diet and overall health goals. Most people will get all the protein they need from their diet alone. On average, it is estimated that a person who is generally sedentary very limited physical activity should consume 0.

This number increases with the amount of physical activity. Aerobic exercise demands a higher protein intake. On the other hand, someone who does mainly strength training will require 1. The recommended intake for protein average individuals was collected from the Nutrient Reference Values Australia and New Zealand.

Brain requires all the necessary nutrients to function efficiently and healthy. This includes. RELATED — Diet and the Brain: Fats. Proteins are also important for aiding the development of necessary chemicals for signal transmission.

It is important to remember that proteins are the building blocks of tissues, bones and muscles so it is no surprise that protein aids in the healing process.

A study conducted on mice found that eating a diet high in protein increased branched chain amino acids. These branched-chain amino acids are also called essential amino acids , and they build muscle, decrease muscle fatigue and soreness.

During a brain injury, neuronal excitation and inhibition is affected. The consumption of protein is thought to restore balance to these neurons by creating more neurotransmitters, and enhancing brain performance.

This can occur after the brain has sustained an injury. Research was conducted to investigate the relationship between supplementation of whey protein and inflammation and stress markers caused by ischemic stroke. This study found that whey protein, containing a rich source of branched-chain amino acids, can significantly decrease inflammation markers in patients with ischemic stroke.

Specific proteins can have different effects on the brain. Netrin is an important protein in the body which strengthens connections in the brain cells. Research on adult rat brains has revealed that netrin can strengthen neural connections in the hippocampus which is responsible for memory and cognitive function.

Clusterin , on the other hand, which is produced after exercise, is a protein that is responsible for enhancing brain cognition. The study found that the existence of anti-inflammatory factors is transferable from exercising mice and can benefit the brain of sedentary mice by boosting memory and dampening brain inflammation.

Mu-opioid receptors are responsible for modulating food intake. Researchers have found that peptides, made by the digestion of proteins, can block these receptors, causing a lack of appetite. Source: Magkos, F.

Reviews in Endocrine and Metabolic Disorders 21 The peptides send signals to the brain that are then transmitted to the gut to stimulate the release of glucose which suppresses the need to eat.

This was tested on mice, it was found that when genetically engineered mice without mu-opioid receptors were fed a high protein diet there was no change in appetite. As most neurotransmitters are synthesized by amino acids, this suggests that protein has an important function in the health and role of neurotransmitters.

A study on mice found that protein deficiency can cause abnormal physiological changes in the brain. These changes can decrease neurotransmitter levels. Increasing the protein intake is thought to reverse this decrease but further research is needed to fully understand the mechanisms.

Tyrosine is an amino acid that has important roles in creating chemicals like. Increasing dopamine, adrenaline and noradrenaline may improve memory and performance in stressful situations.

In the previous section, we saw that optimum protein diets enhance brain performance. Tryptophan is an essential amino acid that is used to produce serotonin which is important for mood. The depletion of tryptophan, due to low protein intake, can affect the production of serotonin.

This, in turn, can negatively affect mood and cause aggressive behavior. A study conducted on women found that tryptophan depletion correlates to aggression.

The women in the study were given amino acid drinks containing either balanced tryptophan or depleted tryptophan. The results found that women who consumed the tryptophan depleted drink were more easily aggravated when provoked. Protein RbAp48, produced by our body, is known to interact with histones which are crucial for memory consolidation.

Physical activity, dietary supplements or pharmaceuticals could be used to increase protein RbAp Lack of this certain protein in young mice showed that the mice were unable to form robust memories of novel objects and locations.

A study of 14 boys with ADHD and 13 boys without ADHD looked at the fibroblast cells to understand the transport of tyrosine, tryptophan and alanine.

It found that children with ADHD had decreased access to tryptophan and elevated access of alanine in the brain. A decrease in tryptophan may cause disturbances in the neurotransmitter system. Research conducted on rats discovered that when rats have a protein deficiency and lack certain proteins, they are more susceptible to a drug which causes epiletic seizures.

It is thought that diets with low protein result in lack in essential amino acids which may trigger a seizure. The study found that mice fed a low protein diet showed more anxiety-like behaviors when compared to those fed the control diet. Another research performed on mice found that consuming a low protein diet can lead to learning disabilities and impulsive and hyperactive behavior.

A low protein diet may cause low blood amino acid levels which results in a neurotransmitter deficiency in the brain.

This decrease in neurotransmitter is thought to be the cause of the decrease in cognitive function. This is demonstrated in humans with an investigation on older adults.

Proteins are also used in the production of hormones. Hormones produced by the pituitary gland mostly use proteins as their building blocks. Low protein diets have been linked to low hormone levels including growth hormones and estrogen.

This is demonstrated by a study on mice. When protein was removed from their diet, there was a decrease in Follicle-Stimulating hormone FSH and Luteinizing hormone LH. The concern of a high protein intake and negative effects to the brain is that the protein may be replacing carbohydrates which are also important for brain health.

However, it is highly unlikely that any individual can consume enough excess protein to cause extreme health issues. Brain fog is the diminished mental capacity or inability to concentrate clearly. There are many factors that can cause brain fog such as.

However, brain fog can also be caused by excess intake of protein. When the protein intake increases, the carbohydrate intake decreases causing a sugar deficit. RELATED — Diet and the Brain: Our brain on sugar.

Brain shrinkage can occur naturally in humans due to aging. But, cell loss can occur due to brain injury, infections or medical conditions such as dementia.

Amino acids are the building blocks of protein and play an important role in building proteins, hormones and neurotransmitters. Each protein is made up of a combination of amino acids.

The arrangement of amino acids determines the different shapes and functions of the protein.