Many of us feel frustrated by low energy, poor focus, and a changeable mood. This is further compounded when you seem to be sleeping reasonably well, eating “normally”, yet still battling mid-morning brain fog or a 3pm energy crash.
Somewhere along the way, someone has probably suggested that you increase your protein.
But can protein genuinely improve cognitive function, or is this just another over-simplified nutrition claim?
To explore this properly, we spoke to London-based Registered Health Coach and Applied Functional Medicine Practitioner Villy Tsvetkova. Villy has over 10 years’ experience in the private wellness sector and specialises in supporting people not only to cope, but to truly thrive.
Her perspective is measured and refreshingly realistic: protein may help, but not in the way many people assume.
Why Protein Is Often Linked to Better Energy and Focus
Protein is frequently associated with mental clarity and sustained energy. According to Villy, that link isn’t accidental, but it is often misunderstood.
“Protein tends to be linked with energy and focus because it plays several supportive, behind-the-scenes roles in how the body and brain function,” she explains. “It provides amino acids, which are the building blocks used to make many important compounds involved in alertness and mental clarity.”
Protein also contributes to energy stability. Compared to meals made up largely of refined carbohydrates, protein-containing meals are generally more sustaining. Studies in certain groups of people have shown that protein slows digestion and gastric emptying, which means that energy is released over time. This may mean that having a high-protein meal doesn’t lead to the rapid spikes and crashes that other foods or meals can cause.
That steadiness is often what people interpret as “better energy” or improved cognitive function. It isn’t a surge, and instead it feels like a smoother ride.
Why Common Claims Miss the Mark
One of the most common claims is that more protein boosts energy instantly.
“That framing can be misleading,” says Villy. “Protein doesn’t act like caffeine, so it doesn’t create a noticeable surge in alertness.”
Another misconception is that simply adding protein will automatically fix brain fog or low mood. In reality, energy and focus are influenced by sleep quality, stress load, hormonal changes, total calorie intake, and overall diet composition, not a single macronutrient.
Protein can support the foundations of steadier energy, but it can’t override chronic sleep deprivation or sustained stress.
Protein Doesn’t Act Like a Stimulant – and That’s the Point
Caffeine works by stimulating the central nervous system, temporarily reducing the perception of fatigue. The effect is quick and noticeable.
Protein works differently. “Protein doesn’t stimulate the nervous system,” Villy explains. “Instead, it provides amino acids that support normal brain and body function. The impact is subtler, more like steady foundational support rather than a noticeable lift.”
Understanding this distinction matters. When people expect a dramatic “boost”, they may assume protein isn’t working if they don’t feel an immediate change.
When you think about energy crashes vs steady energy, it’s the steadier energy that is often more supportive of consistent concentration and emotional regulation. It’s less dramatic, but far more sustainable.
How Protein Can Support Energy and Focus Indirectly
Protein’s influence on mental energy is largely indirect. Rather than stimulating the brain, it supports several physiological processes that underpin day-to-day functioning.
Supporting Stable Blood Sugar Levels
When protein is included as part of a balanced meal, it slows digestion and moderates how quickly glucose enters the bloodstream. This contributes to more stable blood sugar regulation and fewer spikes and crashes.
This stability may mean fewer mid-morning or mid-afternoon crashes; the kind that leave you foggy, irritable, or reaching for something sweet.
As Villy puts it: “It’s not about controlling blood sugar in a clinical sense. It’s about smoothing out the everyday fluctuations that affect how you feel.”
Providing Building Blocks for Brain Chemistry
Proteins are broken down into amino acids which act as precursors for neurotransmitters, the chemical messengers involved in attention, motivation and emotional stability.
Let’s look at two amino acids:
tryptophan is the precursor to serotonin, which influences mood and sleep
Tyrosine is the precursor to dopamine, adrenaline, and noradrenaline, which play roles in motivation and alertness
This does not mean eating protein directly changes your mood in the moment. But adequate protein intake helps ensure the body has the raw materials required for normal neurotransmitter production.
Reducing Energy Dips Through Satiety
Protein also enhances satiety more effectively than carbohydrate-dominant meals.
When you feel satisfied for longer, you’re less likely to experience intense hunger. This steadier appetite pattern can reduce the cycle of reactive eating that often contributes to energy crashes.
Again, this supports stability rather than pushing energy levels artificially higher.
What Protein Can – and Cannot – Do for Mood
Protein supports the biological foundations that help regulate mood. By contributing to neurotransmitter production and energy stability, it may reduce some physiological triggers that make mood feel more fragile, such as sharp crashes or erratic eating patterns.
However, protein does not treat anxiety, depression, or other mental health conditions.
“Mood is influenced by psychological, social, hormonal and lifestyle factors,” says Villy. “Protein plays a supportive role within that bigger picture, but it isn’t a solution on its own.”
Clear expectations prevent disappointment. Nutrition framed as a quick fix often leads to frustration. Protein is a foundation that supports resilience over time, and having this view encourages a more balanced, realistic perspective.
Why Some People Don’t Feel a Difference
Not everyone notices a change when increasing protein intake, and there can be several reasons for this.
If your protein intake was already adequate, increasing it further may not produce a noticeable effect. Protein supports normal function; once needs are met, adding more doesn’t necessarily translate into feeling different.
Find out more: How Much Protein Do Adults Actually Need?
Low energy is rarely caused by a single factor. Sleep, stress, hormonal shifts, total energy intake and overall dietary pattern all play roles.
Consistency also matters more than isolated changes. “The body benefits from steady patterns over time, not one higher-protein meal,” Villy notes.
If you’re unsure why you haven’t felt a difference, it may be helpful to read our related article on why some people don’t feel the benefits of protein straight away, which explores this in more depth.
When Protein Is Most Likely to Support Day-to-Day Mental Energy
Protein is most likely to feel supportive when:
meals previously relied heavily on refined carbohydrates
energy crashes are linked to long gaps between meals
overall protein intake has been inconsistent
sleep and stress are reasonably well managed
Adding protein into regular, balanced meals can help with both satiety and sustained energy, which can be particularly useful for avoiding dips or crashes.
Villy also notes that: “As we age, the body loses muscle mass faster which can lead to a condition called sarcopenia. Women can experience a gradual reduction in skeletal muscle size and strength from their mid-30s onwards.”
“Research shows that consuming less than the recommended daily allowance (RDA) of protein – 0.8 grams per kilogram of body weight per day (g/kg/day) – accelerates this loss. However, the RDA is not optimal for many women. Having a higher protein intake of 1.2-1.6g/kg/day has been linked to better muscle retention.”
Research also suggests our protein needs increase with age, with some evidence supporting intakes of 1.2-2.0g/kg/day to preserve muscle mass in elderly adults.
While this article is not about protein targets, adequate intake becomes increasingly important as part of maintaining overall physiological resilience, which indirectly supports cognitive and emotional stability, too.
Protein as Part of an Energy-Supportive Diet – Not a Standalone Solution
“It helps to view protein as a steady, supportive building block or one piece of a foundation. Alongside adequate sleep, regular nutrient-rich meals, sufficient total energy intake, and a varied diet, protein contributes to steadier physiological function,” Villy reminds us.
“Our bodies are designed to operate well within certain biological parameters. When our foundational requirements are broadly met, systems tend to work more smoothly. And when they work more smoothly, we generally feel better.”
Consistency matters far more than a single higher-protein meal. Over time, protein can contribute to energy stability, sustained focus, and everyday resilience, and you are more likely to benefit from ongoing balanced dietary patterns.
