Coming Soon

Would you like to be notified when we release the For Her portion of Prime?

Mental Changes for Men at 40


Article at a Glance

  • Fatigue, depression, insomnia, memory changes, and low libido can all be symptoms of an aging brain.
  • Symptoms may be subtle in your 40’s, but it’s the decade in which changes to the physical structure of the brain may first lead to some change in cognitive power.
  • There are several science-backed methods that can reduce the impact of aging on the mind.

Do you feel like your memory isn’t as sharp, your concentration wavers, your energy levels have dipped, and you’re just not feeling like yourself? If so, age-related mental changes may be behind it all.

In this article, we’ll be covering some of the notable mental changes a 40-year-old man may experience and some research-backed ways you can take control of your mind and mitigate the effects of aging.

The Brain’s Structure and Function

The brain is made up of cells called neurons. Neurons communicate with each other via neurotransmitters to convey signals that ultimately lead to a response.

How quickly a signal is transmitted from one neuron to the next depends on whether a neuron has a myelin sheath, which makes the signal travel a lot faster. The neurons that have a myelin sheath collectively are referred to as white matter, while those that don’t are called gray matter.

The brain is divided into sections, called lobes, each of which is in charge of certain functions. For example, the frontal lobe of the brain controls skills such as memory, language, attention, and motion [R].

Physical Changes of the Brain

Physical changes in the brain are often what precede the mental changes seen with age. The volume and weight of the brain decline by about 5% per decade after the age of 40, partially due to the progressive death or shrinkage of neurons in the gray matter. White matter is also affected by aging- after the age of 40, the myelin sheaths start to deteriorate, primarily affecting the neurons in the frontal lobe [R].

One way to slow down the negative physical changes that happen in the brain is through the consumption of Omega-3 fatty acids, which are effective at fostering brain repair and enhancing neurogenesis (the production of more neurons) [R].

A Decrease in Processing Speed

Any stimulus that comes at us, be it visual, auditory, or tactile, is received by our brain, which then processes and responds to it. The speed with which a response happens is referred to as processing speed, which is known to progressively decline with age [R].

How can you keep your brain working at high-speed? The combination of supplements lutein and zeaxanthin improve many cognitive functions, including processing speed, by improving communication between neurons [R]. There are also types of cognitive training, particularly processing speed training games, found to improve cognitive processing speed [R].

Memory Decline

At age 40, otherwise healthy men likely don’t have any serious age-associated memory problems. However, between the ages of 45-49, the first signs of memory loss may start appearing [R].

Different subtypes of memory are localized in different areas of the brain. Most notable is the hippocampus, which is a key region involved in memory formation [R]. Cell loss that occurs in the hippocampus in an age-dependent manner is one of the reasons memory declines [R, R]. This cell loss is part of normal aging but can also lead to the development of neurodegenerative diseases such as Alzheimer’s disease.

Another cause for declining memory is the reduction in the neurotransmitter dopamine with age. Dopamine levels drop at a rate of 10% per decade, starting in early adulthood [R]. Among many other functions, this neurotransmitter is involved in memory production in the hippocampus. When less dopamine is available, memory formation is not as strong.

Yet another cause for changes in memory is the production of proteins called beta-amyloid. High levels of beta-amyloid lead to the creation of a sticky mass in the brain that is tightly linked with memory loss seen in Alzheimer’s disease [R,R].

Improving dopamine levels can reduce the extent of age-related memory decline. Ways to enhance dopamine include massage therapy and meditation, which were shown to increase dopamine production by 31% and 65%, respectively [R, R].  Recent studies show that omega-3 fatty acids promote the clearance of beta-amyloid from the brain and enhance memory performance  [R, R].

Impaired Sleep

 Sleep is intricately linked to mental health. Symptoms of decreased sleep include not only sleepiness during the day, but also depressed mood, poor memory, and impaired concentration [R].

As we age, impaired sleep becomes increasingly common and is a major contributing factor to fatigue and depression. With age, deep sleep duration decreases, while nighttime awakenings increase, leading to poor sleep [R].

In addition, insomnia related to emotional stress becomes more common in middle-aged men. This means during periods of stress, middle-aged men are more sensitive to the sleep disturbances caused by stress hormones, such as cortisol [R].

What are some ways you can improve your sleeping patterns? Zinc supplements are effective in improving sleep quality and duration [R,R]. In addition, melatonin supplementation has been shown to improve the onset, duration, and quality of sleep [R].

Testosterone Levels Change

Testosterone is a hormone that decreases with age at a rate of 1%-2% per year after the ages of 30-40 [R,R]. Testosterone has a strong effect on cognition. Research on middle-aged men shows an association between lower levels of testosterone and poor cognitive performance, memory loss, depression, fatigue, low libido, and insomnia [R, R].

Low testosterone levels can be managed through weight loss, sleep improvement, stress reduction and testosterone replacement therapy [R][R]. Researchers found that testosterone replacement therapy can lead to significant improvements in cognitive functioning, and it’s particularly effective in lowering depression scores in men with low testosterone [R].

Protecting Overall Cognition 

Optimizing diet and exercise, which positively affects many areas of health, can also support cognition. For example, the Mediterranean diet is well documented for its health benefits, which includes reducing the risk of cognitive impairment [R].

And physical exercise, while strengthening the body, also strengthens the mind. It induces both structural and functional changes, leading to improved cognitive functioning and overall wellbeing. Physical exercise also provides protection against neurodegeneration, the loss of structure and function of neurons [R]. Cardiovascular exercises, in particular, increase both blood flow and the amount of oxygen going to the brain. This improves neuron formation and helps maintain brain volume [R].

Finally, whole-body cryotherapy, the health modality that is quickly gaining in popularity, was found to significantly improve feelings of well-being, elevate mood and induce relaxation [R, R].


In your forties, you’re likely still in the clear for many of the potential age-associated mental changes. But it’s a great time to try some of the above methods to reduce potential future impact.

Check out our list of longevity and health clinics to start harnessing the resources available to slow mental aging.

The information on this website has not been evaluated by the Food & Drug Administration or any other medical body. Information is provided for educational purposes. You should consult your doctor before acting on any content on this website.

We're committed to being the most trusted online review community on the market.