Life Extension Magazine®

Plant ingredients can help reduce brain fog

Wipe Away Brain Fog

Fuzzy thinking? In separate clinical trials, two plant ingredients reduced mental fatigue, boosted attention levels and improved aspects of memory.

By Michael Downey.

Have you had days when thinking seemed "fuzzy" and you couldn't concentrate?

If it interferes with daily life, you may be suffering from brain fog.1,2

Brain fog refers to an overall feeling of decreased focus and low mental energy.

After pinpointing biological changes in the brain that may trigger brain fog, researchers identified two plant-based nutrients that can prevent or reverse these changes to boost alertness and mental sharpness.

In clinical trials, mango leaf extract:3,4

  • Improved reaction time,
  • Reduced mental fatigue,
  • Boosted attention,
  • Increased performance accuracy, and
  • Enhanced working memory.

In additional clinical studies, peppermint oil:5

  • Reduced development of mental fatigue,
  • Improved aspects of memory, and
  • Boosted attention levels.

Taken together, mango leaf extract and peppermint oil may help replace that fog with focus.

Origins of Brain Fog

Brain fog is more than an annoyance. The feeling of mental fatigue, difficulty concentrating, and foggy thinking can impair cognitive performance and get in the way of school, work, family time or day-to-day activities.

To understand brain fog better, scientists studied medical conditions that produce some of the same mental symptoms.

Complaints consistent with brain fog have been reported by people with:2,6-12

  • Various inflammatory disorders,
  • Allergies (including seasonal allergies),
  • Immune disorders, which increase inflammation, and
  • Dietary sensitivities.

After analyzing the biological alterations associated with these conditions, scientists proposed that brain fog may be caused by:6-8,13

  • Release of histamine (the chemical that causes allergic symptoms),
  • Inflammation, and
  • Neurotransmitter imbalance and impairments in neuronal activity.

Reversing Harmful Changes

Based on this research, scientists began studying compounds that met two criteria:

  • They could prevent or reverse the biological alterations seen in conditions that lead to brain fog, and
  • They have been shown in animal or human studies to improve symptoms of brain fog.

They identified two plant-derived ingredients that met both of these conditions and seemed the most promising:

  • Mango leaf extract has been clinically shown to improve reaction time, mental fatigue, attention, performance accuracy, and working memory,3,4 and
  • Peppermint oil has been clinically shown to reduce mental fatigue and improve aspects of attention and memory.5

Mango Leaf’s Protective Effects

Mango leaf has long been used in Asia and Africa to treat fatigue. It has neuroprotective, anti-inflammatory, and anti-diabetic properties, which scientists suggest may help prevent brain fog. 3

These effects are believed to be largely attributable to the polyphenol compound mangiferin.

In animal and human studies, mangiferin showed a capacity to protect the brain by:3,14-18

  • Decreasing neuroinflammation,
  • Reducing oxidative stress,
  • Providing neurotransmitter support,
  • Preventing cognitive and memory impairment,
  • Improving key brain fog symptoms, and
  • Exhibiting anti-allergic properties.

What You Need to Know

Fight Brain Fog

  • Brain fog is the feeling of reduced mental energy, clarity, focus, and performance.
  • Preclinical studies show that mango leaf extract and peppermint oil each counter the underlying mechanisms thought to contribute to brain fog.
  • In clinical studies, mango leaf extract and peppermint oil improve symptoms of brain fog, reducing mental fatigue and improving attention, memory, and cognitive performance.
  • A combination of these two ingredients may maximize their brain-supporting power and help lift brain fog.

Clearing Mental Fog

To explore the ability of mango leaf to treat symptoms of brain fog, scientists conducted controlled human trials.

In one study, healthy adults were randomized into four groups. Each group was given one of the following:3

  • Mango leaf extract containing 60% mangiferin,
  • Caffeine,
  • Mango leaf extract and caffeine, or
  • A placebo.

The mango leaf extract group had, compared to baseline:3

  • A striking 47% reduction in fatigue, and
  • An almost 5% improvement in reaction time.

These results were significantly greater than those observed with caffeine alone or with a combination of caffeine and mango extract.

Additionally, brain electrical activity tests showed that taking mango leaf extract increased activity in regions associated with attention, complex cognitive processing, and memory.3

In another clinical study, healthy young adults took either 300 mg of mango leaf extract or a placebo.

The mango leaf improved several areas of cognitive function, including aspects of:4

  • Attention,
  • Performance accuracy, and
  • Working memory.

Improvements were also accompanied by a more relaxed mood. This is critical, because many people who take caffeine to counter brain fog find that it increases nervousness and jitters.

These findings demonstrate that mango leaf extract boosts brain activity, decreases mental fatigue, and supports mental focus and performance.

Peppermint’s Brain Effects

The herb peppermint has traditionally been used to promote digestion and induce calm.

Placebo-controlled studies have shown that plants rich in monoterpenes provide cognitive benefits.19-21 Peppermint oil contains many compounds from this group, including menthol and menthone.21

Human studies show that peppermint teas:22

  • Improve memory, and
  • Boost mental alertness.

In addition, mint species have shown the ability to modulate various neurotransmitters in the brain, such as acetylcholine and GABA, which play roles in cognition, mood, and mental alertness.5

Boosting Brain Power

In a clinical trial, healthy adults took either peppermint oil containing 60% monoterpenes or a placebo.5

Tests were administered to assess aspects of memory, attention, and mood.

Participants who took the peppermint oil showed significant benefits, including:5

  • Reduced development of mental fatigue, and
  • Enhanced aspects of attention and working memory.

By contrast, those who took the placebo were fatigued within a few hours after performing various cognitive tasks.5

Taking peppermint oil and mango leaf extract together may maximize their ability to banish brain fog.


Two plant-based ingredients can improve symptoms of brain fog.

Mango leaf extract and peppermint oil have each been shown in clinical studies to help bring back mental clarity, energy, and focus.

Combined, they may help reduce, or even eliminate, symptoms of brain fog.

If you have any questions on the scientific content of this article, please call a Life Extension Wellness Specialist at 1-866-864-3027.


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