Skip to Main Content

Optimizing Sleep with Alpha-lactalbumin 

Alpha-lactalbumin | Man laying down in bed to rest

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 ( This may be through the known impact of sleep on metabolic systems, including blood pressure, glucose homeostasis, and hormone regulation.  

Figure 1. Recommended hours of sleep per day by age group 

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.  

Figure 2. Tryptophan’s path to enhancing melatonin

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

Figure 3. TRP per serving

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.  


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.  

Impact of Milk Protein Source on Nutrient Digestibility & Calf Performance

Defining the nutritional and functional differences between skim milk powder and whey protein concentrate and exploring the effects of these milk protein sources on nutrient digestibility and performance in calves.

Young calf in a nursery for cows in a dairy farm. Newborn animal. No peple.

Calf milk replacer (CMR) is fed to a majority of the dairy calves in the United States in place of whole milk because it is often more economical, provides convenience and consistency, and lowers risk of disease transmission from unpasteurized milk. Many CMRs are made exclusively from dairy ingredients due to the calf’s innate ability to efficiently digest, absorb, and utilize the nutrients that naturally exist in ingredients of dairy origin.

Research into products to replace whole milk began in the mid-20th century and primarily utilized casein, skim milk, and whey as protein sources. As reviewed in Kertz et al. (2017), the prevailing thought of the time was that quality of protein within a milk replacer was directly related to the ability of the milk replacer to form a clot in the abomasum, and that poor-quality CMR would not form clots in the abomasum, resulting in diarrhea and reduced calf performance. Given that CMRs formulated with dried skim milk powder (SMP) readily clot in the abomasum due to the presence of casein and CMRs formulated with whey protein concentrate (WPC) do not clot in the abomasum due to the absence of casein, one might assume that CMR formulated with SMP would result in improved health and digestibility in calves. A review by Logenbach and Heinrichs (1998) dispels this myth and states that factors other than clotting are responsible for observed differences in calf performance.

This paper defines the nutritional and functional differences between SMP and WPC and explores the effects of these milk protein sources on nutrient digestibility and performance in calves.


While both WPC and SMP originate from whole milk, they are derived through very different forms of milk processing. Dried WPC is a co-product of the cheesemaking process – liquid whey is separated from curds during the cheesemaking process and subjected to ultrafiltration and drying, resulting in various whey protein concentrates containing 34-80% crude protein. Dried SMP, in contrast, results from the separation of cream from milk for butter manufacturing – the resulting skim milk is dried to produce a 34% crude protein ingredient. A key difference among these ingredients is that SMP contains all proteins found in milk, whereas WPC does not contain casein because casein is utilized in the cheesemaking process. As a result, the amino acid profiles of whey protein and skim milk protein differ slightly.

Historically, skim milk was a prime candidate for inclusion in CMR – it was readily available and inexpensive compared to whole milk. More recently, there has been an emergence of skim milk protein use in human and sports nutrition, which has driven the cost of SMP higher and precluded use of much SMP in modern CMR in the United States. In contrast, whey was long considered a waste product with little to no value. As soon as technology allowed for efficient collection and use of whey proteins, milk replacer manufacturers were quick to adopt WPCs in CMR, and WPC is now one of the most commonly used ingredients in CMR due to its excellent nutritional value, high digestibility, and relatively low cost. Heinrichs et al. (1995) surveyed milk replacer use in the United States and reported that approximately 90% of CMRs sampled did not clot in the presence of rennet, indicating little to no casein-containing ingredient inclusion. Another 8% of CMRs sampled formed only a soft clot, indicating 5% of less of the protein in the CMR being derived from casein-containing ingredients. Only 2% of sampled CMRs formed firm clots in the presence of rennet, suggesting very little usage of casein-based ingredients such as SMP in most CMRs.


Several studies have evaluated nutrient digestibility and calf performance when feeding CMR containing WPC and/or SMP. Terosky et al. (1997) fed calves CMRs containing 0, 33, 66, or 100% of protein from either WPC or SMP through 8 weeks of age and measured calf performance and nutrient digestibility (Table 1). The authors reported no difference in bodyweight gain, average daily gain (ADG), dry matter intake (DMI) or feed efficiency with increasing WPC inclusion. Apparent digestibility also did not differ across treatments. There was also no difference in number of scour days per calf between treatments.

Table 1. Performance and nutrient digestibility in calves fed CMR containing 0,33,66 or 100% of protein as WPC or SMP, Adapted from Terosky et al., 1997.

A study conducted by Lammers et al. (1998) fed diets similar to those above in two trials until 6 weeks of age. Results are shown in Table 2. In the first trial, calves were fed CMR only, and in the second trial, calves were fed CMR plus ad libitum calf starter. When calves were fed CMR only, ADG and feed efficiency were improved with increasing WPC inclusion, and there was no difference in DMI or scour days per calf among treatments. When calves were fed CMR and calf starter, there were no differences in DMI, ADG, feed efficiency, or scour days per calf among treatments.

Table 2. Growth and performance in calves fed CMR containing 0, 33, 67 or 100% of protein as WPC or SMP, Adapted from Lammers et al., 1998.

A more recent study by Marsh and Boyd (2011) reported no difference in weaning weight, 12 week weight, coat bloom score, ADG, DMI, or feed efficiency when Holstein bull calves were fed CMR containing protein from either SMP or WPC. Finally, Petit et al. (1988) sought to determine if clotting ability of CMR affected nutrient digestibility. Calves were fed either a control CMR containing SMP, or the control CMR with added oxalate, an anti-clotting factor that does not denature milk proteins. As shown in Table 3, there was no difference in dry matter, protein, or fat digestibility when calves were fed identical CMR that clotted or did not clot, disproving the notion that CMR quality was linked to ability of CMR to form a clot in the abomasum.

Table 3. Dry matter protein, and fat digestibility in calves fed either clotting or non-clotting CMR containing SMP

Taken as a whole, these data suggest that WPC provides similar digestibility and calf performance to SMP, and that ability of protein to clot in the abomasum is not indicative of nutrient digestibility.


While casein-containing ingredients such as skim milk were first on the scene in CMR formulation due to low cost and high availability, they have all but been replaced with more cost-effective whey based protein sources such as WPC. Despite differences in ability of these protein sources to form clots in the abomasum, substituting WPC for SMP has little to no impact on calf performance – nutrient digestibility, intake, calf growth, and feed efficiency are maintained. Whey-based protein sources such as WPC are a cost-effective, ideal ingredient for inclusion in CMR.

MSG Acquires Kay’s Processing, Inc.

Milk Specialties Global (MSG), an industry-leading manufacturer of nutritional ingredients for the health and wellness, performance nutrition and functional food industries, has acquired the 96,000-square-foot, gluten-free certified Kay’s Naturals Processing facility, located in Clara City, Minnesota, along with the Kay’s Naturals consumer brand.

Milk Specialties Global plans to expand operations at the Clara City facility to accommodate demand for extruded protein products, which are used for a wide variety of applications ranging from snacks to meat alternatives. To ensure business continuity, the facility’s current employees have received offers to remain with the facility, and additional jobs will be created in the future to support production expansions. “There is a lot of potential to ramp up production and increase capacity at our new Clara City facility, including more co-manufacturing,” says MSG Vice President of Extrusion Technology and Strategy Jim Fischer. “This acquisition will expand our extruded protein capabilities and help us better meet the needs of our customers.”

The Clara City plant is part of MSG’s long-term expansion strategy. The newly named Milk Specialties Global Clara City Facility is MSG’s 11th plant, and the latest in a series of strategic acquisitions and expansions that began in 2008. Most recently, in 2020 the company doubled its lactose production following expansion of its west coast processing facility in Visalia, CA. Earlier this year, MSG completed a capital improvement project at its Fond Du Lac, WI facility to begin production of lactoferrin, signaling the launch of its NutriPRO™ line of products focusing on the health benefits of whey protein. “MSG has one of the best protein supply chains in the world and great infrastructure for producing high-quality products,” says MSG CEO David Lenzmeier. “With each investment, we can offer more value for our customers.”

Media Note: For additional information or to schedule an interview, contact Media Relations, Inc. at 952-697-5221.

About Milk Specialties Global
Milk Specialties Global (MSG) is an industry-leading manufacturer of nutritional ingredients for the health and wellness, performance nutrition and functional food industries, with manufacturing facilities in WI, MN, NE, IL and CA. The core of MSG’s business is in high-percentage protein ingredients (whey protein concentrates, isolates and hydrolysates, as well as milk protein concentrates, isolates and micellar casein), lactose and permeate as well as value added ingredients. Additional information about Milk Specialties Global, including the benefits of its proprietary processing methods, can be found on