Effect of whey protein on blood lipid profiles: a meta-analysis of randomized controlled trials

The functionalities and applications of whey/whey protein in fermented foods: a review

Whey, a major by-product of cheese production, is primarily composed of whey protein (WP). To mitigate environmental pollution, it is crucial to identify effective approaches for fully utilizing the functional components of whey or WP to produce high-value-added products. This review aims to illustrate the active substances with immunomodulatory, metabolic syndrome-regulating, antioxidant, antibacterial, and anti-inflammatory activities produced by whey or WP through fermentation processes, and summarizes the application and the effects of whey or WP on nutritional properties and health promotion in fermented foods. All these findings indicate that whey or WP can serve as a preservative, a source of high-protein dietary, and a source of physiologically active substance in the production of fermented foods. Therefore, expanding the use of whey or WP in fermented foods is of great importance for converting whey into value-added products, as well as reducing whey waste and potential contamination.

Benefits of Whey Proteins on Type 2 Diabetes Mellitus Parameters and Prevention of Cardiovascular Diseases

Type 2 diabetes mellitus (T2DM) is a major cause of morbidity and mortality, and it is a major risk factor for the early onset of cardiovascular diseases (CVDs). More than genetics, food, physical activity, walkability, and air pollution are lifestyle factors, which have the greatest impact on T2DM. Certain diets have been shown to be associated with lower T2DM and cardiovascular risk. Diminishing added sugar and processed fats and increasing antioxidant-rich vegetable and fruit intake has often been highlighted, as in the Mediterranean diet. However, less is known about the interest of proteins in low-fat dairy and whey in particular, which have great potential to improve T2DM and could be used safely as a part of a multi-target strategy. This review discusses all the biochemical and clinical aspects of the benefits of high-quality whey, which is now considered a functional food, for prevention and improvement of T2DM and CVDs by insulin- and non-insulin-dependent mechanisms.

Cow's Milk in Human Nutrition and the Emergence of Plant-Based Milk Alternatives

Cow's milk is considered a complete food, providing high-quality protein and essential micronutrients, including vitamins and minerals. For medical reasons or as a lifestyle choice, consumers are replacing cow's milk with plant-based milk alternatives (PBMA); some perceive them as healthier alternatives to cow's milk due to their low saturated fatty acid content and no cholesterol content. However, the nutritional composition of PBMA is quite variable between different types and even within, which makes a comparison with cow's milk a complex issue. Furthermore, the consumption of PBMA has been associated with the development of some diseases in infants and children. Meanwhile, the consumption of cow's milk in human health is a controversial issue since it has been associated with a favorable effect in some diseases (such as obesity, type 2 diabetes, and Alzheimer's) and a negative effect in others (such as prostate cancer risk and Parkinson's disease); while in some diseases, there is no consensus in the cow's milk consumption effect. The aim of this review is to make a nutritional comparison of cow's milk with PBMA and to clarify the potential health issues related to their consumption.

Effects of Whey Protein or Its Hydrolysate Supplements Combined with an Energy-Restricted Diet on Weight Loss: A Randomized Controlled Trial in Older Women

An energy-restricted weight-loss approach has limitations when it used in the elderly, especially because of muscle loss. We aimed to assess the effects of whey protein (WP) or WP hydrolysate (WPH) combined with an energy-restricted diet (ERD) on weight reduction and muscle preservation in older women with overweight and obesity. A total of 60 women were randomized to the control (ERD), WP (ERD + 20 g/d WP) or WPH (ERD + 20 g/d WPH) group, using a 1:1:1 allocation ratio. After an 8-week intervention, body composition, gut microbiota, and serum metabolomics changes were compared among the three groups. The reductions in body weight (−1.11 ± 1.11 vs. −2.34 ± 1.35, p < 0.05), BMI (−0.46 ± 0.45 vs. −0.97 ± 0.54, p < 0.05), and body fat (−0.70 ± 0.92 vs. −2.45 ± 1.65, p < 0.01) were higher in the WPH group than in the control group. Body fat (%) was significantly decreased in the two protein groups. Fat-free mass did not significantly change among the three groups. Serum metabolomics showed that the tricarboxylic acid cycle pathway was upregulated in the WPH group. No significant changes in microbiota were observed among the groups. In conclusion, WP or WPH supplementation combined with an energy-restricted diet benefits older women during weight loss. WPH was more effective, possibly due to increased energy metabolism.

No adverse effects of dairy products on lipid profile: A systematic review and meta-analysis of randomized controlled clinical trials

BACKGROUND AND AIMS

The current study aimed to review the effects of dairy foods on lipid profile in randomized controlled clinical trials (RCTs).

METHODS

We searched PubMed, Scopus, Embase, and Central. RCTs that assess the effects of dairy foods on lipid profile were included.

RESULTS

The overall effects of dairy foods on lipid profile were non-significant. Dairy foods were associated with a non-significant reduction in triacylglycerol level, and a non-significant increase in total cholesterol, low density lipoprotein cholesterol, and high-density lipoprotein cholesterol level.

CONCLUSION

We conclude that dairy foods doesn't have any unfavorable effects on lipids.

Whey Protein Supplementation Improves the Glycemic Response and May Reduce Non-Alcoholic Fatty Liver Disease Related Biomarkers in Women with Polycystic Ovary Syndrome (PCOS)

Polycystic ovary syndrome (PCOS) increases type 2 diabetes and non-alcoholic fatty liver disease (NAFLD) with insulin resistance. We hypothesized that a 35 g whey preload would improve insulin sensitivity and glucose handling while reducing biomarkers associated with NAFLD. Twenty-nine age-matched women (CON = 15, PCOS = 14) completed oral glycemic tolerance tests following baseline (Day 0) as well as an acute (Day 1) and short-term whey supplementation (Day 7). Whey had an interaction effect on glucose (p = 0.02) and insulin (p = 0.03), with glucose remaining stable and insulin increasing with whey supplementation. Insulin sensitivity (p < 0.01) improved with whey associated with increased glucagon secretion (p < 0.01). Alanine aminotransferase (ALT), and aspartate aminotransferase (AST) remained unchanged, but “day” had an effect on the AST:ALT ratio (p = 0.04), whereas triglycerides and sex hormone binding globulin overall were greater in the PCOS group (p < 0.05). Total cholesterol decreased in PCOS (by 13%) and CON (by 8%) (NS). HepG2 cells treated with plasma from participants before and after whey decreased lipid accumulation in the PCOS group after whey (p < 0.05). Whey provided an insulinogenic and glycemic homeostatic effect in women with PCOS with the potential to combat NAFLD-consequences.

Effects of whey protein plus vitamin D supplementation combined with progressive resistance training on glycaemic control, body composition, muscle function and cardiometabolic risk factors in middle-aged and older overweight/obese adults with type 2 diabetes: A 24-week randomized controlled trial

AIM

To determine the effect of whey protein plus vitamin D supplementation combined with progressive resistance training (PRT) on glycaemic control, body composition, muscle function and cardiometabolic risk factors in middle-aged and older adults with type 2 diabetes (T2D).

MATERIALS AND METHODS

In this 24-week, randomized controlled trial, 198 overweight/obese adults (aged 50-75 years) with T2D undertook PRT (2-3 days/week) with random allocation to whey protein (20 g each morning plus 20 g postexercise) plus vitamin D₃ (2000 IU/day) (PRT + ProD, n = 98) or no supplementation (PRT, n = 100). Primary outcomes were HbA1c and homeostatic model assessment-2 of insulin resistance (HOMA2-IR). Secondary endpoints included fasting plasma glucose (FPG), body composition, muscle strength, physical function, blood pressure, blood lipids and inflammatory markers.

RESULTS

At 24 weeks, supplementation did not enhance the effects of PRT on HbA1c (mean absolute change: PRT + ProD -0.10% [95% CI, -0.24%, 0.05%] vs. PRT -0.17% [95% CI, -0.32%, -0.03%], p = .322) or HOMA2-IR (PRT + ProD -0.12 [95% CI, -0.27, 0.03] vs. PRT -0.03 [95% CI, -0.14, 0.09], p = .370). There were also no significant between-group differences for the mean changes in the secondary outcomes, except that FPG improved in PRT versus PRT + ProD (net difference, 0.6 mmol/L [95% CI, 0.1, 1.0], P = .018), while interleukin IL-10 (61% [95% CI 31%, 92%], P < .001), tumour necrosis factor-α (16% [95% CI, 3%, 29%], p = .015) and 30-s sit-to-stand performance (number, 1.0 [95% CI, -0.05, 1.5], p = .047) increased in PRT + ProD versus PRT.

CONCLUSIONS

In older overweight/obese adults with T2D, daily whey protein plus vitamin D supplementation did not augment the effects of PRT on measures of glycaemic control, body composition, muscle strength or cardiometabolic risk factors.

Whey peptides exacerbate body weight gain and perturb systemic glucose and tissue lipid metabolism in male high-fat fed mice

Consumption of milk-derived whey proteins has been demonstrated to have insulin-sensitizing effects in mice and humans, in part through the generation of bioactive whey peptides. While whey peptides can prevent insulin resistance in vitro, it is unclear whether consumption of whey peptides can prevent obesity-induced metabolic dysfunction in vivo. We sought to determine whether whey peptides consumption can protect from high fat (HF) diet-induced obesity and dysregulation of glucose homeostasis. Male C57BL/6J mice were fed either a low or HF diet for 13 weeks. HF diet fed mice were provided drinking water with no addition (control), undigested whey protein isolate (WPI, 1 mg ml^-1) or whey protein hydrolysate (WPH, 1 mg ml^-1) throughout the diet regimen. Mice consuming WPH gained more body weight and were more glucose intolerant compared to those consuming WPI or water only. Despite increased body weight gain, perigonadal adipose tissue weight and lipid accumulation were unchanged. However, excess lipids accumulated ectopically in the liver and skeletal muscle in mice consuming WPH, which was associated with elevated inflammatory markers systemically and in adipose tissue, liver, and skeletal muscle. In skeletal muscle, mitochondrial fat oxidation and electron transport chain proteins were decreased with WPH consumption, indicative of mitochondrial dysfunction. Taken together, our results demonstrate that WPH, but not WPI, exacerbates HF-induced body weight gain and impairs glucose homeostasis, which is accompanied by increased inflammation, ectopic fat accumulation and mitochondrial dysfunction. Thus, our results argue against the use of dietary whey peptide supplementation as a preventative option against HF diet-induced metabolic dysfunction.

Effects of protein supplementation on muscle wasting disorders: A brief update of the evidence

OBJECTIVE

To examine the effects of protein supplementation on muscle mass, strength and function in individuals at risk of muscle wasting disorders.

METHODS

A narrative overview of the literature based on a PubMed search.

RESULTS

Increasing protein intake beyond the recommended dietary intake may prevent or attenuate muscle loss in people at risk of muscle wasting disorders; however, there is inconsistent evidence for any benefits on muscle strength or physical function. This is likely due to the significant heterogeneity and bias regarding baseline demographics, basal protein/energy intakes and protein supplement type, dose, timing and compliance.

CONCLUSION

Protein supplementation attenuates muscle loss in some populations at increased risk of muscle wasting, but there is no consistent evidence to support benefits on muscle strength or physical function. Further randomised controlled trials are needed that focus on whether there is an optimal type, dose and timing of protein intake, and potential interaction with other nutrients.

Effects of whey protein on glycemic control and serum lipoproteins in patients with metabolic syndrome and related conditions: a systematic review and meta-analysis of randomized controlled clinical trials

Background

This systematic review and meta-analysis aimed to assess the effects of whey protein on serum lipoproteins and glycemic status in patients with metabolic syndrome (MetS) and related disorders.

Methods

Online databases, such as Web of Science, Cochrane Library, PubMed and Scopus were systematically searched by two independent authors from inception until 30th April 2020 for English randomized clinical trials investigating the efficacy of whey protein administration in subjects with Mets or related conditions on the parameters of glycemic and lipid control compared to certain control. In order to evaluate the included studies’ methodological quality, Cochrane Collaboration risk of bias tool was applied. Using Cochrane’s Q test and I-square (I²) statistic, the included trials’ heterogeneity was also examined. Using a random-effects model, data were pooled, and weighted mean difference (WMD) was considered as the overall effect size.

Results

Twenty-two studies were selected to be included in this meta-analysis. Consumption of whey protein resulted in significant reduction of HbA1c (WMD: -0.15; 95% CI: − 0.29, − 0.01) insulin (WMD: -0.94; 95% CI: − 1.68, − 0.21) and homeostasis model assessment-estimated insulin resistance (HOMA-IR) (WMD: -0.20; 95% CI: − 0.36, − 0.05). A significant reduction in triglycerides levels (WMD: -17.12; 95% CI: − 26.52, − 7.72), total cholesterol (WMD: -10.88; 95% CI -18.60, − 3.17), LDL-cholesterol levels (WMD: -8.47 95% CI: − 16.59, − 0.36) and total cholesterol/HDL-cholesterol ratio (WMD: -0.26; 95% CI: − 0.41, − 0.10) was found as well.

Conclusions

This meta-analysis suggests that supplementation with whey protein had beneficial effect on several indicators of glycemic control and lipid parameters in patients with MetS and related conditions.

Effect of dietary supplementation of whey powder and Bacillus subtilis on growth performance, gut and hepatic function, and muscle antioxidant capacity of Japanese quail

This experiment was conducted to evaluate the effects of dietary supplementation of whey powder (WP), Bacillus subtilis (BAS), and their combination (MIX) on growth performance, intestinal morphology, caecal microflora, hepatic gene expression, blood metabolites, and skeletal muscle antioxidant capacity in Japanese quails. A total of 400 one-day-old Japanese quails were randomly distributed to 20-floor pens (4 dietary treatments, 5 replications per treatment, 20 birds per pen). The birds were fed a basal diet (control, CON) or the basal diet supplemented with 40 g/kg WP, 1 g/kg BAS probiotic or 40 g/kg WP plus 1 g/kg BAS probiotic for five weeks. Feed intake was not affected by the treatments at any stage of the trial. However, the WP, BAS, and MIX feed had better weight gain and feed conversion ratio compared to the CON during the entire production period (day 1-35; p < .05). Feeding the WP, BAS, and MIX diets caused no significant difference in morphometric measures in the duodenum, jejunum, and ileum other than the villus height to crypt depth ratio in the ileum (p < .05). The expression of insulin-like growth factor-1 (IGF-1) and growth hormone genes was highly upregulated in the liver of the birds fed the MIX diet (p < .05). Feeding birds with the diets containing WP, BAS, and MIX increased the population of caecal lactic acid bacteria and reduced serum cholesterol concentration compared to the CON diet (p < .05). Likewise, the tested feed additives increased superoxide dismutase and glutathione peroxidase enzyme activities in the thigh muscle (p < .05). No synergistic effect was found between WP and BAS in studied parameters other than IGF-1 gene expression. Improved growth performance of Japanese quails by feeding the WP, BAS, and the MIX feed could be linked to improved absorptive capacity of the small intestine as well as over-expression of anabolic growth factors. In conclusion, WP with or without BAS could be considered as a beneficial dietary supplement to enhance productive performance, gut functionality, and antioxidant capacity of Japanese quail.

Health Benefits of Whey or Colostrum Supplementation in Adults ≥35 Years; a Systematic Review

Food-health claims are an important method of translating nutrition research to consumers. Whey and colostrum are thought to exert health benefits to adults, but it is unclear what measurable, objective health benefits they impart. This review aimed to identify the objective health benefits of bovine whey or colostrum-based beverages to healthy adults aged ≥35 years to substantiate a food-health claim. Seven databases were systematically searched. Eligible articles were RCTs that involved healthy adults aged ≥35 years, consuming whey or colostrum in beverage form and measuring objective health markers. Quality assessment and data extraction was conducted in duplicate. The searches identified 9943 papers and 16 were included in this review; 13 studies, reported across 15 papers, related to whey, one study to colostrum. The outcomes identified were body composition, bone mineral density, biochemical markers, such as blood glucose and lipids, and muscle strength and synthesis. Heterogeneous outcomes, high risk of bias and inconsistent findings resulted in inconclusive evidence to substantiate a food-health claim. Clearer reporting and consensus on a minimum set of objective measures would allow for more robust recommendations regarding food-health claims. Protecting consumers from misleading health claims will require collaboration between regulators, researchers, and the food industry.

The effect of whey protein on the components of metabolic syndrome in overweight and obese individuals; a systematic review and meta-analysis

BACKGROUND

The risk of developing chronic diseases such as diabetes, cardiovascular disease, dyslipidemia, and stroke is increased following an outbreak of metabolic syndrome. Whey protein can play a major role in preventing metabolic syndrome.

OBJECTIVE

This study was conducted to systematically evaluate the effect of whey protein on the components of metabolic syndrome in overweight and obesity patients.

METHODS

This systematic review and meta-analysis was conducted on RCTs (PROSPERO registration number: CDR42019114794). Published articles of controlled trials between 1 January 2000 to 30 May 2019 indexed in PubMed, Scopus, Web of Science and Cochrane Library were reviewed. Keywords were Whey Protein, Metabolic Syndrome, HDL Lipoprotein, Blood Pressure, Triglyceride, Fasting Blood Glucose, Waist Circumference, Overweight and Obesity or a combination of them in the title/abstracts. The mean difference was extracted for each study. All analyses performed using STATA version 11.

RESULTS

There were 2344 individuals reviewed in this systematic review of 37 published articles.

CONCLUSION

According to the results, whey supplementation significantly reduced the SBP, DBP, HDL, waist circumference, TG and FBS in intervention groups in comparing to control groups.

Beneficial effects of running and milk protein supplements on Sirtuins and risk factors of metabolic disorders in rats with low aerobic capacity

Background

Physical activity and dietary intake of dairy products are associated with improved metabolic health. Dairy products are rich with branched chain amino acids that are essential for energy production. To gain insight into the mechanisms underlying the benefit of the sub-chronic effects of running and intake of milk protein supplements, we studied Low Capacity Runner rats (LCR), a rodent exercise model with risk for metabolic disorders. We especially focused on the role of Sirtuins, energy level dependent proteins that affect many cellular metabolic processes.

Methods

Forty-seven adult LCR female rats sedentary or running voluntarily in wheels were fed normal chow and given supplements of either whey or milk protein drink (PD)-supplemented water, or water only for 21 weeks. Physiological responses were measured in vivo. Blood lipids were determined from serum. Mitochondrial markers and Sirtuins (Sirt1-7) including downstream targets were measured in plantaris muscle by western blotting.

Results

For the first 10 weeks whey-drinking rats ran about 50% less compared to other groups; still, in all runners glucose tolerance improved and triglycerides decreased. Generally, running induced a ∼six-fold increase in running capacity and a ∼8% decrease in % body fat. Together with running, protein supplements increased the relative lean mass of the total body weight by ∼11%. In comparison with sedentary controls, running and whey increased HDL (21%) and whey, with or without running, lowered LDL (−34%). Running increased mitochondrial biogenesis and Sirtuins 3 and 4. When combined with exercise, both whey and milk protein drink induced about a 4-fold increase in Sirt3, compared to runners drinking water only, and about a 2-fold increase compared to the respective sedentary group. Protein supplements, with or without running, enhanced the phosphorylation level of the acetyl-coA-carboxylase, suggesting increased fat oxidation. Both supplemented diets increased Sirt5 and Sirt7 without an additional effect from exercise. Running diminished and PD supplement increased Sirt6.

Conclusion

We demonstrate in rats new sub-chronic effects of milk proteins on metabolism that involve Sirtuins and their downstream targets in skeletal muscle. The results show that running and milk proteins act on reducing the risk factors of metabolic disorders and suggest that the underlying mechanisms may involve Sirtuins. Notably, we found that milk protein supplements have some favorable effects on metabolism even without running.

•

Interactive effects of running and/or milk protein supplements were studied.

•

Milk protein drink enhanced and whey diminished the amount of voluntary running.

•

Despite less running whey-supplementation improved metabolic health.

•

Almost all Sirtuins in muscle adapted to milk protein and running interventions.

Whey Protein Combined with Low Dietary Fiber Improves Lipid Profile in Subjects with Abdominal Obesity: A Randomized, Controlled Trial

Abdominal obesity is associated with elevated postprandial triglycerides (TG), an independent risk factor for cardiovascular diseases. Previous studies show that whey protein (WP) and dietary fiber may separately reduce postprandial TG. However, few studies have investigated the long-term effects of WP and dietary fiber on postprandial TG. We aimed to investigate the separate and combined long-term effects of WP and dietary fiber from wheat bran on postprandial TG and markers of lipid metabolism in subjects with abdominal obesity. We conducted a 12-week, double-blind, randomized, controlled, parallel intervention study. In a 2 × 2 factorial design, 73 adults were randomized to receive 60 g/day of either WP hydrolysate or maltodextrin (MD) combined with high-fiber wheat bran products (HiFi; 30 g dietary fiber/day) or low-fiber refined wheat products (LoFi; 10 g dietary fiber/day). A high-fat meal test was conducted before and after the intervention. Sixty-five subjects were included in the final analyses. There were no differences between intervention groups in postprandial TG assessed as incremental area under the curve (iAUC). WP-LoFi had reduced postprandial TG assessed as total area under the curve (tAUC) and reduced fasting TG compared with all other groups, and reduced fasting apolipoprotein B-48 compared with MD-LoFi. There were no changes in lipoprotein lipase activity. Total cholesterol and apolipoprotein B-100 were reduced after WP intake compared with MD. Total cholesterol was increased after HiFi intake compared with LoFi. In conclusion, intake of WP in combination with low-fiber cereal products for 12 weeks had beneficial effects on postprandial TG tAUC and fasting TG, but not on postprandial TG iAUC in subjects with abdominal obesity. Combining WP with high-fiber wheat bran products did not improve lipid profile.

High-fat diet leads to adiposity and adipose tissue inflammation: the effect of whey protein supplementation and aerobic exercise training

There is little understanding about dietary proteins and their potential contribution to obesity-induced inflammation. This study investigates the effect of 10 weeks of aerobic training and whey protein (WP) supplementation on visceral adipose tissue inflammation in rats fed a high-fat diet (HFD). In the first phase, which lasted 9 weeks, 40 male Wistar rats were randomly divided into 2 groups: (1) normal diet (n = 8), and (2) HFD (n = 32). In the second phase, rats fed an HFD were randomly assigned into 4 groups (n = 8/group): (1) sedentary, (2) WP, (3) aerobic training, and (4) WP + aerobic training. The aerobic training was performed for 10 weeks, 5 days/week at 21 m/min, 15% incline, for 60 min/day. HFD significantly increased body weight, adiposity index, fat pads weight, glucose levels, and insulin resistance index compared with the normal diet. Also, levels of tumor necrosis factor alpha (TNF-α), monocyte chemoattractant protein-1 (MCP-1), hypoxia inducible factor 1 alpha (HIF-1α), and vascular endothelial growth factor A (VEGF-A) in adipose tissue and serum levels of TNF-α were increased in the HFD group. Glucose levels, insulin resistance index, and triglycerides were reduced only by WP, independently of aerobic training. Both the aerobic training and WP reduced the fat pads weight and levels of TNF-α, HIF-1α, and VEGF-A in adipose tissue. Nevertheless, the levels of MCP-1 in adipose tissue and serum levels of TNF-α and MCP-1 were not reduced significantly by WP or aerobic training. These findings suggest that both aerobic training and WP supplementation lead to a reduction in adiposity and ameliorate obesity-induced inflammation in visceral adipose tissue.

The role of whey protein in postprandial glycaemic control

Epidemiological studies demonstrate that poor glycaemic control is an independent risk factor for CVD. Postprandial glycaemia has been demonstrated as a better predictor of glycated Hb, the gold standard of glycaemic control, when compared with fasting blood glucose. There is a need for more refined strategies to tightly control postprandial glycaemia, particularly in those with type 2 diabetes, and nutritional strategies around meal consumption may be effective in enhancing subsequent glycaemic control. Whey protein administration around meal times has been demonstrated to reduce postprandial glycaemia, mediated through various mechanisms including an enhancement of insulin secretion. Whey protein ingestion has also been shown to elicit an incretin effect, enhancing the secretion of glucose-dependent insulinotropic peptide and glucagon-like peptide-1, which may also influence appetite regulation. Acute intervention studies have shown some promising results however many have used large dosages (50-55 g) of whey protein alongside high-glycaemic index test meals, such as instant powdered potato mixed with glucose, which does not reflect realistic dietary strategies. Long-term intervention studies using realistic strategies around timing, format and amount of whey protein in relevant population groups are required.

Supplementation of fermented Maillard-reactive whey protein enhances immunity by increasing NK cell activity

Objective: The objective of this study was to investigate the impact of supplementation with fermented Maillard-reactive whey protein (F-MRP) on natural killer (NK) cell activity, circulating cytokines, and serum protein levels.