Aging is an inevitable process for everyone. As we age, the effects of aging and inputs such as stress, poor diet, lack of exercise, inadequate sleep, and brain trauma all begin to have compounding effects on an individual’s energy levels and cognition.
In this article, we’re going to discuss the science behind aging and how certain nootropics could help delay the cognitive deficits which come with age.
What Is Aging?
A commonly accepted definition of aging put forward by gerontologist Michael R Rose in his 1991 book Evolutionary Biology of Aging, is “A persistent decline in the age-specific fitness components of an organism due to internal physiological deterioration”.
In layman’s terms, it is a time-based, continual breakdown of internal processes that maintain an organism’s ability to survive and reproduce. Our particular focus is on the brain and the processes that allow its ability to perceive, interpret, recall and respond to information, as necessary to maintain quality of life and normal daily function in the aging individual.
The effects of aging accumulate over time, with some apparently directly linked to age itself, while others are more variable in the way they appear and progress, in general, the older an individual is, the more likely it is that many of these effects will be experienced and to a greater degree.
Sleep, Aging, And Cognitive Function
Cognitive function is directly linked to several key functions in daily life, for instance, physical activity. Younger people are generally more active, use more energy, and tend to sleep more as a result.
Inadequate or poor-quality sleep is directly correlated to mental aging and poor cognitive function not only in the young but especially in the aging brain. Studies have shown decreases in the duration and the quality of sleep the average person achieves as they age. Insomnia is widespread amongst the sedentary and the less active and has a direct impact upon thought, memory, energy levels, and even the rate the brain itself is shown to age (1). This is a profile that fits an increasing number of individuals as they age, compounding the aging process of the brain and impacting cognitive function. Beyond adequate exercise and natural sleep-aid hormones such as melatonin, nootropics may provide alternative strategies to combat undesirable effects of aging on the brain.
As individuals age, mild memory loss is common, as are the effects on new learning, focus, processing speed, and clarity of thought. This is a normal part of aging and is experienced at differing rates for each individual. For many, memory loss is little more than an inconvenience, however, for some, this generally slow decline progresses further into Alzheimer’s, dementia, and other debilitating cognitive age-related diseases (2).
Fortunately for most, early cognitive decline is by no means as pronounced or as rapid as in the aforementioned conditions, and is touted to be halted, managed, or reversed for periods of time through the use of beneficial compounds such as nootropics.
It is known that the mechanisms for cognitive decline in aging are many and varied, including:
- Reduced levels of neurotransmitters
- Alterations to cellular signaling pathways such as insulin
- Decreased mitochondrial function leading to diminished cellular energy production
- Structural changes in the brain and associated organs
- Accumulation of toxic cellular products and debris, changes in protein turnover
- Oxidative stress and DNA damage, accompanying other types of metabolic dysregulation (3).
Accordingly, different nootropics may bestow unique and alternate benefits associated with these mechanisms and their effects on cognition in the aging brain. One possible advantage of this is the potential to target different symptoms and mechanisms simultaneously, by combining or ‘stacking’ various nootropics together in a daily regime. Through such an approach it may be possible to achieve precise and customized benefits for the individual.
Nootropics are reported to offer benefits such as improved memory recall, increased focus, greater mental clarity, extra alertness, and faster reaction times, but does this hold true in through the process of aging?
In this article we’ll explore if this is indeed the case, and furthermore, which nootropics in particular are shown to have the greatest benefits for the aging brain.
Nootropics To Aid Cognitive Function In Aging
Caffeine is the most popular and widely used nootropic. Found in tea, coffee, cocoa, dark chocolate, and herbs such as yerba mate, caffeine is well-known for increasing alertness, energy, memory, reaction times and mood in general (4).
The cognitive benefits of caffeine are primarily via the blockade of adenosine receptors which otherwise work to slow impulses within the brain (5).
The amount of caffeine found in a cup of coffee varies between 50-400mg, the average being around 120mg in a double-shot espresso and 150mg in a filter coffee.
Different sources of caffeine may come with accompanying nootropics such as theobromine, theanine and other compounds, offering further direct or synergistic effects when consumed as a whole-extract rather than a pure isolate such as found in caffeine pills or powders (4).
Studies into the effects of caffeine on cognitive protection in older adults have produced mixed results. Recent meta-analyses generally report positive protective benefits from caffeine ingestion (6, 7, 8).
Some studies have noted differences in benefits based on gender. Several studies show greater positive benefits for older women, while cognitive benefits in older men although reported, are less notably observed (9, 10, 11, 12).
While regular doses and common forms of ingestion are considered safe and generally pleasant, pure caffeine products have increasingly come under scrutiny regarding safety due to a number of otherwise healthy individuals suffering from inadvertent overdoses leading to severe side-effects including death.
Caffeine doses within the standard range are considered safe for most individuals, however unwanted side-effects such as anxiety, jitters, or nausea may be experienced with elevated doses. Sleeplessness may occur when consumed within 4-8 hours of bedtime, which may work against desired cognitive benefits if adequate sleep quality or quantity is not achieved.
Although not commonly thought of as a nootropic, creatine is a highly effective cognitive enhancer (13). Acting as a phosphate donor, creatine is able to recharge adenosine triphosphate (ATP), the main cellular currency, which is converted to adenosine diphosphate in the process of fuelling mitochondria which power all cells.
Neurons and muscle cells require especially high amounts of ATP to function optimally. Memory-making has been shown to rapidly deplete phosphocreatine levels in the working-brain even when ATP supplies are sustained. While creatine is synthesized within the body in organs such as liver, kidneys, and pancreas, or obtained via dietary sources such as red meat, fish, and eggs, the body is able to use more creatine daily than either whole-food diet, or synthesis is able to provide.
This is where supplementary creatine is able to fill the gap, providing extra creatine in a form that is easily consumed, and able to be stored within tissues for use as required. Creatine storage decreases as muscle tissue atrophies during aging, resulting in decreased levels of phosphocreatine stored for utilization in skeletal tissues and the brain. However, supplementation has been shown to increase these levels, improving cognitive processing associated with aging, and overall quality of life.
Beyond energy production, creatine has been shown in human trials to have antioxidant effects.
Benefits of creatine supplementation are thought to extend to positive and preventative effects during the early stages of cognitive disorders such as Alzheimer’s, Parkinson’s, Huntington’s, Amyotrophic lateral sclerosis, and stroke (14, 15).
Creatine is one of the most extensively studied dietary supplements ever, is inexpensive, and has an excellent safety profile, offering benefits to all consumers.
Those with kidney disease, diabetes or hypertension are recommended to consult with their physician prior to undertaking a creatine supplementation regime as these conditions may be exacerbated by creatine use, although researchers have concluded this is not likely the case. Creatine supplementation is especially beneficial for those who may obtain inadequate dietary creatine, such as vegetarians and vegans (14).
Standard supplementary doses of creatine range between 2g and 5g daily, with 2g found to be adequate for general maintenance of creatine stores, while 5g doses provide for those with larger overall body-mass or more active and physically demanding lifestyles. Long-term creatine supplementation in aged individuals has been found to be safe without the requirement to periodically cycle-off (16).
Alpha Lipoic Acid (ALA)
Lipoic acid is an omega 3 fatty acid present in both plant and animal-based foods and utilized as a dietary supplement. Alpha lipoic acid has been explored as a means to decrease inflammation, oxidative damage and improving mitochondrial function due to its powerful antioxidant properties, mitochondrial nutritive properties, and its ability to promote cellular recycling of other vital and beneficial antioxidants such as vitamin C.
Animal studies have shown these properties, amongst others, promote memory-improving and neuroprotective effects, with ALA demonstrated to be powerful enough to reverse age-associated decreases of both neurotransmitters and receptors in the aging brain (17).
Although ALA is able to be synthesized within the body, there is evidence to show that this is utilized differently to that which is obtained dietarily, additionally, studies have shown reduced ability to absorb it when consumed as part of a meal containing fatty acids, presumably due to competition with other nutrients. Due to this competition, it is thought that the Western diet is unlikely to provide adequate daily ALA to work as a cognitive enhancer. Supplementation of ALA on its own in an alternate timeframe to meals is a way to avoid this competition and increase daily intake of ALA (18).
ALA is considered safe for long-term oral supplementation at the standard dose of around 600mg per day (18).
Acetyl L-Carnitine (ALCAR)
L-carnitine is a natural brain supplement, a conditionally essential amino acid found in high concentrations in the brain and in muscle tissue. Typically supplemented to assist with energy production and metabolism, particularly fat-burning and as an anti-inflammatory, ALCAR has been demonstrated to decrease oxidative stress particularly in mitochondria, the ‘powerhouse’ of the cell. A precursor for the synthesis of the neurotransmitter acetylcholine, responsible for the transmission of signals between nerves and muscles and declines with age, in its acetylated form, ALCAR crosses the blood-brain barrier more efficiently than L-carnitine and offers improved brain-function, and decreased cognitive decline due to old-age.
Studies show the benefits of ALCAR reach other tissues associated with age-based decline, such as the heart and liver, and has been shown to improve nerve regeneration while being neuroprotective in animal models (3).
In human studies ALCAR has been shown to help with general aging, and even helping those with diseases such as Alzheimer’s, Multiple sclerosis, traumatic brain injuries, as well as those with low-level inflammation of the brain which typically increases as part of the aging process (19).
Doses of ALCAR are typically 2g per day and considered safe. Although beneficial in aged individuals, ALCAR supplementation has not been shown to confer any significant benefit in healthy young adults. ALCAR is commonly stacked with Alpha Lipoic Acid.
Fish Oil (DHA and EPA)
Omega-3 Fatty acids docosahexaenoic acid (DHA) and eicosapentaenoic acid (EPA) are found in high levels in fish-oils. DHA is one of the most abundant polyunsaturated fats within the brain and retina, with a corresponding responsibility for brain growth and development, and proper function of both (20).
EPA has been found to inhibit inflammation that may result from aging or damage. Although DHA is able to be synthesized endogenously from α-linoleic acid derived from diet, this production is very low in humans (21). Accordingly, supplementing DHA has been observed to improve several processes related to aging such as memory, reaction speeds, thinking and overall cognitive function in both healthy individuals, and those experiencing mild cognitive decline (22).
Benefits derived from supplementation of DHA and EPA (as either fish oils or from regular inclusion of fatty fish into the diet) are thought to arise from an increased supply of fatty acids providing for increased membrane maintenance and improved glucose metabolism of neurons.
Although many animal and human trials report cognitive benefits from supplementation of DHA and EPA, particularly in combination, the results are mixed. Some studies report little or no benefit despite short and long-term dosing with doses deemed to be within the optimal range, while others saw decreased loss-of memory only in institutionalized individuals greater than 75 years of age (23). Possible reasons for differences include prior nutritional history, changes in metabolism due to age and particular genotypes (21).
Daily doses of DHA: EPA in clinical trials that reported cognitive benefits vary from as little as 180mg:120mg to as much as 1290mg:450mg and 720mg:1080mg (21). Although generally described as safe, FDA guidelines recommended daily intake of omega-3’s should not exceed 3000mg combined.
Although aging is an inevitable process, the rate of effects it has upon the brain does not have to be.
As outlined above, there are a variety of nootropics available which may be utilized both stand-alone or in combination in order to offset undesired effects of aging upon the brain. Scientific evidence is compelling and growing for the many benefits able to be obtained through these nootropics.
Deciding which nootropic(s) might best suit your requirements may seem a little daunting at first but it doesn’t have to be.
The supplements discussed in this article are affordable, safe, and in the case of a cup of tea or coffee enjoyable to add to a daily routine.
Identifying benefit(s) you most want to access is the easiest way to choose a strategy that is right for you. Whether it’s a boost in energy and brain-power as provided by a quick coffee, ALCAR or a regular dose of creatine, to increased memory as offered by ALA or fish oil, or perhaps a range of payoffs as offered by stacking them as required.