The process of aging causes multiple physiological, psychological and social changes that affect food choice and consumption. Advancing age alters food reward signals, reduces food craving behavior, and suppresses appetite and energy intake, all of which contribute to a condition termed the “anorexia of ageing”. Compared with younger adults, older adults are reported to consume approximately 30% less energy per day. Dietary diversity (the number of different foods or food groups consumed over a given reference period) is also attenuated with ageing, with lower consumption of protein reported in older populations. Inadequate regulation of food and protein intake increases the risk of developing conditions such as sarcopenia and osteoporosis. Therefore, protein-energy homeostasis is considered a fundamental dietary-related determinant of healthy aging.

Dietary protein requirements increase with age, attributed partly to an increase in anabolic resistance to muscle protein synthesis (MPS), which accelerates loss of skeletal muscle mass and function. Maintaining muscle mass is essential to protect against falls, which are a leading cause of injury-related mortality in older people and a consequence of anorexia of ageing.

Despite the highly satiating effects of protein, interestingly, evidence suggests that older adults exhibit a blunted satiety response to protein consumption compared with younger adults. In fact, whey protein drinks have been shown to increase short-term total daily energy and protein intake in older people, even when the protein content of the drinks is very high. Another promising strategy for promoting energy and protein consumption in later life is the fortification of foods with protein. Increasing food volume to meet energy requirements is often unachievable in older groups, therefore, increasing energy and protein density while not affecting or reducing portion size, would be beneficial. As it is frequently reported that older adults consume inadequate amounts of protein, supplementing a healthy diet with additional high-quality protein may sufficiently stimulate MPS, without adversely affecting habitual appetite and food intake. However, further studies investigating compliance with long-term protein supplementation and the effects on satiety and energy intake are warranted.    

With the global population ageing (current UN projections expect 1.5 billion people over the age of 65 by 2050), innovative strategies to support protein-energy homeostasis are essential. Adopting a co-production approach involving academia, industry, practitioners and members of the public may stimulate the design of effective nutritional interventions, which consider age-related changes in physiology, cognition and lifestyle that affect appetite and dietary needs and preferences.

Further references and reading:

Bauer, J., Biolo, G., Cederholm, T., Cesari, M., Cruz-Jentoft, A.J., Morley, J.E., Phillips, S., Sieber, C., Stehle, P., Teta, D. and Visvanathan, R., 2013. Evidence-based recommendations for optimal dietary protein intake in older people: a position paper from the PROT-AGE Study Group. Journal of the American Medical Directors association, 14(8), pp.542-559.

Dent, E., Hoogendijk, E.O. and Wright, O.R., 2019. New insights into the anorexia of ageing: from prevention to treatment. Current Opinion in Clinical Nutrition & Metabolic Care, 22(1), pp.44-51. 

Lonnie, M., Hooker, E., Brunstrom, J.M., Corfe, B.M., Green, M.A., Watson, A.W., Williams, E.A., Stevenson, E.J., Penson, S. and Johnstone, A.M., 2018. Protein for life: Review of optimal protein intake, sustainable dietary sources and the effect on appetite in ageing adults. Nutrients, 10(3), p.360.

Morley, J.E., 1997. Anorexia of aging: physiologic and pathologic. The American journal of clinical nutrition, 66(4), pp.760-773.

Nishimura, Y., Højfeldt, G., Breen, L., Tetens, I. and Holm, L., 2021. Dietary protein requirements and recommendations for healthy older adults–A critical narrative review of the scientific evidence. Nutrition research reviews, pp.1-48.

Breastfeeding is recommended by the World Health Organization as the best option for the developing infant¹. Where breastfeeding is not possible, infant formulas provide a nutritious substitute, with advances in technology enabling more sophisticated formulas to be produced.

Both human and bovine milk are complex matrices of nutrients and bioactive compounds, developed by nature to support growth and development. The protein in both human and bovine milk is composed of two main types: whey and casein, although the ratio of these varies between species; from 60:40 whey:casein in mature human milk, to 20:80 in cows’ milk. Both types of proteins are high quality, meaning they have an excellent essential amino acid profile that is well digested and absorbed by the body.

Whey and casein themselves are composed of different protein fractions and figure 1 shows the differences in whey protein fractions between these milk sources².

Whey proteins in general and their constituent fractions have shown many nutritional and physiological benefits across the lifespan, not least, supporting infant growth and development. During digestion in the small intestine, whey proteins are broken down to amino acids and peptides, with the latter being suggested to exert physiological effects beyond just amino acid absorption.

BENEFITS OF ALPHA-LACTALBUMIN

Sleep-wake cycle

Sleep is critical for infant growth and development, particularly brain development³. Serotonin and melatonin are known to be key regulators of sleep across the lifespan; however, serotonin cannot cross the blood-brain barrier, thus it must be synthesized within the brain. The amino acid tryptophan is a precursor for serotonin and an amino acid able to cross the blood-brain barrier, hence it plays an important role in serotonin production.

The mean concentration of tryptophan in breast milk is around 2.5%, whereas standard formulas are only around 1-1.5%². As discussed later, utilizing bovine alpha-lactalbumin in infant formulas can close this gap, as alpha-lactalbumin rich ingredients are higher in tryptophan than standard whey protein powders.

The influence of tryptophan-rich infant formula on sleep has been demonstrated in clinical trials. In one study, researchers looked at the influence of either tryptophan-rich infant formula during the day with standard formula at night (INV), vs tryptophan-rich formula at night with standard formula during the day (EXP), vs a standard formula control⁴. The standard formula contained 1.5% tryptophan, whereas the experimental formula contained 3.4% tryptophan. The researchers found that the EXP group had a greater total sleep time, better sleep efficiency (total time in the crib/total sleep time), more immobility time, and fewer night movements and waking episodes than the other groups (see figure 3).

Gastrointestinal and Immune Function

The infant gut is immature, and a number of factors influence its development, most notably the nutrients and bioactive compounds found in milk. With protein being a main component of mammalian milk, it’s no surprise this key nutrient influences gut and immune function.

Specifically, alpha-lactalbumin likely exerts some of its beneficial impact on gut development and immune health through the release of bioactive peptides in the small intestine. For example, it has been reported that three of the bioactive peptides released from alpha-lactalbumin, rather than alpha itself, demonstrate anti-microbial properties⁵.

In addition to serotonin’s influence on the sleep/wake cycle and central nervous system, it has also been reported to play a key role in gut motility and immune capability, while tryptophan itself has regulatory roles within the gut².

Differences in the microbiome of breastfed and formula fed infants have been observed, with breastfed infants predominantly showing Lactobacillus and a diverse population of Bifidobacterium, while formula fed infants microbiome is more reflective of adults with more diversity⁶. Meanwhile, peptides from alpha-lactalbumin digestion have been reported to exert prebiotic benefits⁷.

One study investigated the incidence of E-coli induced diarrhea incidents in rhesus monkeys fed either standard formula, alpha-enriched formula or breastmilk⁸. Researchers found that not only were there fewer incidents in the alpha-fed monkeys than those fed standard formula, but this group also did not differ from the breastfed group, highlighting a closer match to the gold-standard recommendation.

A CLOSER MATCH TO MOTHER’S MILK

o ensure sufficient intake of amino acids in standard formulas, the overall protein level has traditionally been higher than that of breastmilk. However, this has been suggested as a cause of some of the longer term metabolic and health differences observed between breastfed and formula fed infants⁹. It is also thought to be a factor in the growth differences observed between breastfed and formula fed infants².

By better matching the protein profile of breastmilk through ingredients such as alpha-lactalbumin, the overall protein content of infant formulas can be lowered, while still meeting infant’s amino acid needs and without compromising growth, development and long term 

health¹⁰.

Although standard bovine whey protein does contain some alpha-lactalbumin (~15-20% of total whey protein), utilization of advanced membrane and processing technologies enables manufacturers to increase the level of alpha-lactalbumin in whey protein ingredients, thus allowing infant formula producers to bring formulations closer to the composition of breastmilk.

This closer matching to breastmilk is supported by the similar amino acid composition of bovine and human alpha-lactalbumin, as shown figure 2.¹¹.

CONCLUSION

Whey protein is composed of several protein fractions, with alpha-lactalbumin being the largest fraction in human milk. Bovine alpha has a very similar amino acid profile to human alpha and utilizing it as an ingredient in infant formula enables growth, development and nutritional support closer to breastfed infants. Alpha has been shown to have a number of benefits, including supporting the sleep-wake cycle, immune system and gut development. Breastfeeding is recommended as the optimal choice for infant growth and development. When this is not possible, sophisticated formulas – such as those containing alpha-lactalbumin – provide a valuable substitute.

---

NutriPRO™ Alpha-lac Offerings

At Milk Specialties Global, our scientists and engineers work relentlessly to create high-quality ingredients designed to optimize health and nutrition. With this in mind, our NutriPRO™ Alpha-Enriched range was developed to enable infant formula manufacturers to provide more sophisticated products that better support infant growth and development. Within this range are both whey protein concentrates and isolates, with 2 to 3 times the level of alpha in standard whey protein.

REFERENCES 

1. Victoria et al (2016). The Lancet, 387:475-490
2. Layman et al (2018). Nutr Rev 76(6):444-460
3. Nieuwenhuizen et al (2008). Br J Nutr 101(12):1859-1866
4. Aparicio et al (2007). Nutritional Neuroscience, 10:3-4, 137-143
5. Pellegrini et al (1999). Biochimica et Biophysica Acta (BBA), 1426(3)
6. Harmsen et al (2003). J Paed Gast Nutr, 30:61-67
7. Kee et al, 1998. Korean J Dairy Sci, 20:61-68
8. Bruck et al (2003). J Ped Gastr Nutr, 37:273-280
9. Sandström et al (2008). Am J Clin Nut, 87 (4):921-8
10. Oropeza-Cej et al (2018). Nutrients, 10:886
11. Lönnerdal and Lien (2003). Nutr Rev, 61(9):295-305

Sarcopenia – the loss of muscle mass and strength that occurs naturally with aging – can be mitigated by ensuring sufficient protein intake. Reducing the rate of muscle loss is a key factor for maintaining a free and active lifestyle in the advancing years. However, since protein is the most satiating nutrient and appetite diminishes with age, it could be supposed that adding more protein to the diet could lead to an overall reduction in calorie and nutrient intake at a time when they are critical.

While the current UK recommended nutrient intake (RNI) for protein is 0.75g per kg body weight, and the US RNI is 46g for women and 56g for men, other groups have recommended higher levels to be optimal for this group, as shown in the table below.

However, many adults are not achieving their optimal intake, with 36% failing to meet the UK recommendations and a monstrous 85% failing to meet the ESPEN recommendations. Furthermore, protein intake tends to be skewed to the evening, though achieving 25-30g protein at each meal and spreading protein intake throughout the day has been shown to be optimal.

A recent study looked at whether adding a daily whey protein supplement in the form of a gel containing 20g whey protein impacted appetite and overall nutrient intake in 50–75-year-olds. In a cross-over design, Tuttiett et al (2021) also investigated whether there was any impact from having the whey gel in the morning after breakfast, or in the evening before bed.

The researchers found that the addition of a gel did not impact overall appetite or habitual macronutrient intake, i.e. they did not alter the amount of protein, fat and carbohydrate they naturally consumed when excluding the contribution from of protein from the gel. However, the gel did increase overall protein intake.

With regards to the timing of protein supplementation, there was no difference in hunger, satisfaction or eating desire between morning and evening feedings. Since protein intake is typical skewed to the evening, a post-breakfast protein supplement can offer a beneficial strategy to increase protein intake at a time when it is typically low.

Further references and reading:
Department of Health. Dietary Reference Values for Food Energy and Nutrients Report of the Panel on Dietary Reference Values of the Committee on Medical Aspects of Food Policy; Report on Health and Social Subjects 41; HMSO: London, UK, 1991.
Bauer, J.; Biolo, G.; Cederholm, T.; Cesari, M.; Cruz-Jentoft, A.J.; Morley, J.E. Evidence-based recommendations for optimal dietary protein intake in older people: A position paper from the PROT-AGE Study Group. J. Am. Med. Dir. Assoc. 2013, 14, 542–559.
Paddon-Jones, D.; Rasmussen, B.B. Dietary protein recommendations and the prevention of sarcopenia. Curr. Opin. Nutr. Metab. Care 2010, 12, 86–90.
International Protein Board. Protein Matters: The Need to Re-evaluate the Adequacy and Application of Protein Requirements. https://www.internationalproteinboard.org/protein-matters/protein-requirements.htm

The process of aging causes multiple physiological, psychological and social changes that affect food choice and consumption. Advancing age alters food reward signals, reduces food craving behavior, and suppresses appetite and energy intake, all of which contribute to a condition termed the “anorexia of ageing”. Compared with younger adults, older adults are reported to consume approximately 30% less energy per day. Dietary diversity (the number of different foods or food groups consumed over a given reference period) is also attenuated with ageing, with lower consumption of protein reported in older populations. Inadequate regulation of food and protein intake increases the risk of developing conditions such as sarcopenia and osteoporosis. Therefore, protein-energy homeostasis is considered a fundamental dietary-related determinant of healthy aging.

Dietary protein requirements increase with age, attributed partly to an increase in anabolic resistance to muscle protein synthesis (MPS), which accelerates loss of skeletal muscle mass and function. Maintaining muscle mass is essential to protect against falls, which are a leading cause of injury-related mortality in older people and a consequence of anorexia of ageing.

Despite the highly satiating effects of protein, interestingly, evidence suggests that older adults exhibit a blunted satiety response to protein consumption compared with younger adults. In fact, whey protein drinks have been shown to increase short-term total daily energy and protein intake in older people, even when the protein content of the drinks is very high. Another promising strategy for promoting energy and protein consumption in later life is the fortification of foods with protein. Increasing food volume to meet energy requirements is often unachievable in older groups, therefore, increasing energy and protein density while not affecting or reducing portion size, would be beneficial. As it is frequently reported that older adults consume inadequate amounts of protein, supplementing a healthy diet with additional high-quality protein may sufficiently stimulate MPS, without adversely affecting habitual appetite and food intake. However, further studies investigating compliance with long-term protein supplementation and the effects on satiety and energy intake are warranted.    

With the global population ageing (current UN projections expect 1.5 billion people over the age of 65 by 2050), innovative strategies to support protein-energy homeostasis are essential. Adopting a co-production approach involving academia, industry, practitioners and members of the public may stimulate the design of effective nutritional interventions, which consider age-related changes in physiology, cognition and lifestyle that affect appetite and dietary needs and preferences.

Further references and reading:

Bauer, J., Biolo, G., Cederholm, T., Cesari, M., Cruz-Jentoft, A.J., Morley, J.E., Phillips, S., Sieber, C., Stehle, P., Teta, D. and Visvanathan, R., 2013. Evidence-based recommendations for optimal dietary protein intake in older people: a position paper from the PROT-AGE Study Group. Journal of the American Medical Directors association, 14(8), pp.542-559.

Dent, E., Hoogendijk, E.O. and Wright, O.R., 2019. New insights into the anorexia of ageing: from prevention to treatment. Current Opinion in Clinical Nutrition & Metabolic Care, 22(1), pp.44-51. 

Lonnie, M., Hooker, E., Brunstrom, J.M., Corfe, B.M., Green, M.A., Watson, A.W., Williams, E.A., Stevenson, E.J., Penson, S. and Johnstone, A.M., 2018. Protein for life: Review of optimal protein intake, sustainable dietary sources and the effect on appetite in ageing adults. Nutrients, 10(3), p.360.

Morley, J.E., 1997. Anorexia of aging: physiologic and pathologic. The American journal of clinical nutrition, 66(4), pp.760-773.

_{^{AUTHOR: LINDSEY ORMOND}}

Milk contains two main types of proteins – casein and whey. Casein accounts for 80% of the protein in milk, while whey contributes around 20%.

Whey protein is renowned for being a staple in the diet of bodybuilders, which is no surprise given its ability to promote muscle growth and maintenance. However, it is now becoming a key part of mainstreams diets as well, given the unrivaled benefits of high-quality whey proteins.

Whey protein contains all the essential amino acids the human body needs in a form that is rapidly and easily absorbed by the body. Whey protein is particularly high in the branched-chain amino acids (BCAAs), especially leucine. This unique BCAA has been shown to trigger muscle protein synthesis, the process by which the body builds and generates new muscle fibers, which is key for everyone of all ages – not just those wanting to get bigger muscles.

The benefits of whey protein go beyond its ability to support muscle tissue; it has been shown to increase satiety, support weight management,manage blood glucose – both in healthy and pre-diabetic subjects – and even help endurance athletes run faster.

Casein, the main protein in milk protein concentrates and isolates, is also a great source of essential amino acids but is absorbed more slowly by the body (graph source: Boirie, Y, et al. Proc Natl Acad Sci USA 1997). This has the benefit of supplying the body with essential amino acids over a longer period and is why casein or milk protein is often found in overnight recovery products.

HIGH QUALITY PROTEINS IN THE PRODUCTS YOU LOVE

Dairy proteins have long been used in many different applications as they have a long shelf life, can be easily incorporated into products and have a neutral taste. The diversity of applications these proteins can be incorporated into is in part due to the range of ingredients available, many of which have been developed for specific products to meet consumer preferences.

IN CONCLUSION

Dairy proteins provide unparalleled nutritional benefits to help consumers reach their sports performance, weight management, lifestyle, and healthy aging goals. The demand for protein-rich foods and supplements continue to skyrocket, as consumers recognize the benefits of incorporating them into their diet through a variety of applications. Not all proteins are created equal, but for consumers looking for the best source of complete amino acid profiles, dairy proteins are unmatched for nutrition and versatility. Embrace the power of dairy!

Sleep is a critical part of our daily routine. We spend about a third of our time doing it and it’s as essential as food and water. Getting sufficient quality and quantity of sleep impacts our day-to-day performance, as well as our long-term health.  

The amount of sleep we need and get reduces with age, from most of a newborn’s day spent with eyes closed, through around 10 hours in preschool and school age, to 7-9 hours for most adults (see figure 1). Older adults tend to need less sleep at around 7-8 hours. However, many adults are not getting their optimal amount and quality of sleep. Between our non-stop world, increasing demands on our time and increased stress and anxiety, it’s no surprise that 50-70million Americans are reported to have sleep or wakefulness disorders (NIH, 2023). It’s even been reported that “undiagnosed sleep apnea alone is estimated to cost the [US] Nation $150 billion annually”. Athletic populations may have a higher level of sleep disturbances due to travel, late night competitions and training commitments.  

Sleep impacts our daily functioning, including reaction time, memory, mood, and physical performance. It is also known to be strongly associated with long term health, with less than 7 hours and more than 9 hours in middle-age being correlated with dementia risk from 70 years of age (Sabia et al, 2023). The same level of under-or over-sleeping has also been reported to potentially increase the risk of metabolic syndrome in young adults aged 18-24 years old (Nutrients | Free Full-Text | The Relationship between Sleep Duration and Metabolic Syndrome Severity Scores in Emerging Adults (mdpi.com)). This may be through the known impact of sleep on metabolic systems, including blood pressure, glucose homeostasis, and hormone regulation.  

Tryptophan’s Influence on Sleep 

As an essential amino acid, tryptophan is required in the diet since the human body cannot make it. Tryptophan, one of the amino acids in the diet that can cross the blood-brain barrier, is a precursor to serotonin, a neurotransmitter in the body that influences the sleep-wake cycle, mood, cognitive function and much more. This neurotransmitter is then converted into the hormone, melatonin (see figure 2). The uptake of tryptophan into the brain is also influenced by the level of other amino acids in the diet.  

Some foods are richer in tryptophan, as highlighted below. Amongst some of the highest dietary sources is the whey protein fraction, alpha-lactalbumin.   

Alpha-lactalbumin for enhanced sleep and overnight recovery 

Alpha-lactalbumin and tryptophan have been tested for various measures of overnight recovery, sleep quality and quantity, morning wakefulness and cognitive performance. Essentially, it’s been tested to see if it improves sleep and favorably impacts performance the following day.  

Some early work from Hartmann et al (1979) tested 250mg, 500mg or 1g tryptophan supplementation 20minutes before bedtime in those with longer sleep latencies (the time taken to fall asleep) of more than 30minutes. They found that supplementation with 250mg of tryptophan tended to reduce sleep latency and significantly increased the minutes in slow wave sleep.  

Markus et al (2005) found that evening alpha-lactalbumin intake caused a 130% increase in Trp:LNAA before bedtime, and “modestly but significantly reduced sleepiness and improved brain-sustained attention processes the following morning”. Furthermore, in poor sleepers, this was accompanied by improved behavioral performance.  

More recent work looked at whether supplementing semi-professional female rugby union players 2 hours before bed with for the duration of the season impacted any measures of sleep, including total sleep time, sleep efficiency, sleep onset latency and wake after sleep onset (Gratwicke et al, 2023). Alpha was found to reduce sleep onset latency compared to placebo, in particular during bye weeks (weeks with no competition) and during weeks of away games.  

While MacInnes et al did not see an effect of acute alpha-lactalbumin intake in elite or serious recreational cyclist on either sleep quality or performance, this may have been due to the short intervention period.  

Alpha-lactalbumin – more than just a source of tryptophan  

Alpha-lac is the second most abundant fraction in whey protein and, as we know, whey protein has an unrivalled essential and branched-chain amino acid composition, being one of the highest sources of leucine available. While alpha does provide additional leucine compared to a standard whey, this invaluable array of amino acids gives something extra special – high quality protein the muscles and body thrive on.  

While casein or milk protein is most commonly used in overnight recovery products, whey protein was recently shown to be as effective as caseinate for muscle protein synthesis when taken prior to bedtime (Trommelen et al, 2023).  

NutriPRO™ Alpha  

Milk Specialties relentless quest for optimal ingredient solutions led to the addition of alpha-lactalbumin to our portfolio. With a number of product offerings available for multiple applications, please contact us to learn more about how to utilize our ingredient expertise for your products.  

References 

CDC, Sleep and Sleep Disorders, 2023 

Chaudhry et al. Nutrients. 2023;15(4):1046 

Gratwicke et al. Biol Sport. 2023;40(2):449-455 

Hartmann and Spinweber. J Nerv Mental Dis. 1979; 167(8) 

MacInnis et al. Int J Sport Nutr Exerc Metab. 2020;30(3):197-202 

Markus et al. Am J Clin Nutr. 2005;81(5):1026-1033 

NIH, Sleep Science and Sleep Disorders, 2023 

Sabia et al. Nat Commun. 2021;12(1):2289 

Trommelen et al. Sports Med. 2023;10.1007/s40279-023-01822-3.