Protein and Brain Function: Can High-Quality Protein Improve Cognitive Performance?

Weighing roughly three pounds, the majority of the brain is composed of fat. The other 40% consists of water, carbohydrates, salt and — surprisingly enough — protein.

Accordingly, it’s important to nourish your brain with macronutrients, like protein, carbs and fat, to support short- and long-term brain function and maintain the structure of brain cells. Learn how a higher protein intake might be conducive to optimal brain function.

Understanding How the Brain Functions

The brain is an incredibly complex organ that enables cognitive processes such as attention, language, perception, emotion, thought and memory. The function of the brain extends beyond cognition, however. It also communicates with the rest of the body via electrical signals and chemical messengers to maintain homeostasis and regulate various physiological processes.

For example, the autonomic nervous system, a division of the nervous system, regulates involuntary actions like heartbeat and digestion. The hypothalamus, a region of the brain, plays a key role in maintaining internal balance by controlling body temperature, thirst and hunger.

Additionally, the brain influences physical sensations and movements. Motor areas of the brain coordinate muscle contractions and movements, allowing us to walk, talk and perform various tasks. Sensory areas process information from the environment, allowing us to perceive sensations such as touch, taste, smell, sight and sound.

In order to perform these tasks, the brain requires nutrients, including ample protein sources.

How Does Protein Support Brain Function?

It's widely understood that proteins are integral for building and maintaining muscles and organs, facilitating tissue repair and producing essential brain chemicals.

When ingested, dietary proteins are broken down into amino acids within the digestive system. Your body needs 20 of these amino acids to function properly, and nine must be obtained through the food you eat.

Specifically, the central nervous system, which includes the brain, requires amino acids to create neurotransmitters and neuromodulators. Neurotransmitters are chemical messengers that transmit signals across synapses, the junctions between neurons. They can excite or inhibit the activity of neighboring neurons, influencing various physiological and cognitive processes.

Neuromodulators, on the other hand, are substances that can alter the sensitivity of neurons to neurotransmitters or regulate the release of neurotransmitters. They help adjust how neurons communicate, control how flexible connections between neurons are and change the overall activity of brain networks.

The most well-studied amino acids in brain function include:

• Tryptophan – This amino acid is the precursor of serotonin, a neurotransmitter that regulates mood, cognition, learning, memory and reward. As such, tryptophan levels in the brain can affect behavior. Specifically, tryptophan may decrease levels of alertness, feelings of sadness, aggression and uncomfortable physical sensations while also increasing levels of tiredness, which may reduce stress.
• Tyrosine – Tyrosine may also affect behavior by way of its impact on brain neurotransmissions. When the brain is under stress, certain neurons become more active and may need more tyrosine to function properly. As such, this amino acid is important for producing neurotransmitters like dopamine and norepinephrine, which play key roles in how the brain responds to stress and regulates behavior.
• Histidine – This amino acid is involved in the synthesis of histamine, a neurotransmitter that regulates arousal, attention and the sleep-wake cycle. Histamine also plays a role in the immune response and brain inflammation processes.
• Arginine – Arginine is a precursor to nitric oxide, a signaling molecule that regulates blood flow, neurotransmission and synaptic plasticity in the brain. Nitric oxide is involved in various physiological processes, including memory function, learning and neuroprotection.

These four amino acids are found in both plant protein and animal protein-rich foods like chicken, turkey, fish, eggs, legumes and dairy products. Dive deeper into the role of amino acid vs protein.

Aging, Protein and Brain Function

Beyond protein’s function in the production of neurotransmitters and neuromodulators, a study published in The American Journal of Clinical Nutrition suggests that higher protein intake may also prevent cognitive decline as you age.

The study observed the eating habits of 77,000 men and women over the course of 20 years. Those who ate more proteins in their diet than carbohydrates experienced more cognitive benefits. Specifically, researchers concluded that with each 5% increase in calories obtained from animal protein rather than carbohydrates, there was an associated 11% decrease in the risk of losing memory, language and problem-solving abilities. Further, with every 5% increase in plant protein, there was a 28% decrease in the risk of later-in-life cognitive decline, such as that related to conditions like Alzheimer's Disease.

How Much Protein Do You Need?

To support full-body health, including brain health, the Recommended Dietary Allowance (RDA) is 0.36 grams of protein per pound. So, if you weigh 200 pounds, you should aim to eat at least 72 grams of protein throughout the day.

That said, the RDA applies to sedentary adults, meaning, if you’re active, you should likely follow a high protein diet to adequately maintain and build muscle mass.

When filling your shopping cart with protein-rich foods, remember to incorporate foods that contain essential amino acids, which the body can only obtain through diet. These dietary proteins include meat (beef, pork, lamb), poultry (chicken, turkey), fish (tuna, salmon), dairy products (milk, cheese, yogurt), eggs, rice, wheat and legumes (beans, lentils).

The nine essential amino acids include:

• Histidine – As mentioned, histidine is a precursor to histamine, which is involved in regulating arousal, attention and the sleep-wake cycle. Histamine also plays a role in the immune response and brain inflammation.
• Isoleucine – Isoleucine is involved in synthesizing neurotransmitters and regulating energy metabolism in the brain. It also supports cognitive function and mood regulation.
• Leucine – Leucine is important for protein synthesis and muscle repair. It also regulates blood sugar levels and supports brain function by providing energy to neurons.
• Lysine – Lysine is involved in synthesizing neurotransmitters and collagen, which is essential for maintaining the structure and integrity of brain cells. It also demonstrates the beneficial relationship between protein and immune system function.
• Methionine – Methionine is a precursor to other amino acids and is involved in synthesizing neurotransmitters like serotonin and dopamine. It also supports liver function and detoxification processes in the brain.
• Phenylalanine – Phenylalanine is a precursor to tyrosine, which is further converted into neurotransmitters like dopamine and norepinephrine. These neurotransmitters play key roles in mood regulation, focus and attention.
• Threonine – Threonine is involved in synthesizing proteins and supporting the immune system. It also plays a role in producing glycine, an inhibitory neurotransmitter that promotes relaxation and sleep.
• Tryptophan – As previously explored, tryptophan is a precursor to serotonin, a neurotransmitter that regulates mood, cognition, learning, memory and reward. Adequate levels of serotonin are important for maintaining a stable mood, reducing feelings of sadness and aggression and promoting relaxation and sleep.
• Valine – Valine is involved in protein synthesis and muscle repair. It also contributes to energy production in brain cells and helps maintain cognitive function and mood stability.

Support Your Brain Health With INVIGOR8

Supplying your body with enough dietary protein sources can help support optimal brain function, ensuring that your cognitive processes, such as attention, memory function and mood regulation, are at their best.

The INVIGOR8 Superfood Shake, our organic superfood powder supplement, provides a convenient way to incorporate high-quality whey protein and cognitive enhancers like L-theanine into your diet, helping you stay focused, energized and mentally sharp throughout the day. If you're looking to amp up your low protein intake, look no further than this meal replacement shake, also available in our all-in-one weight loss kits, today!

Sources:

1. Johns Hopkins Medicine. Brain Anatomy and How the Brain Works
2. Cleveland Clinic. Amino Acids
3. Harvard Health Publishing. Protein intake associated with less cognitive decline
4. Harvard Health Publishing. How much protein do you need every day?
5. Healthline. Essential Amino Acids: Definition, Benefits, and Food Sources