Myth Bust Monday

You can only absorb 30 grams of protein/meal

This is a myth!

Can you only absorb 30 G protein/meal for muscle protein synthesis? Probably not.

A study done by Tipton et al. (2016) shows otherwise:

 

Study type:

2-group, randomized, double-blind, crossover design.

Amount:

Group 1- 20 g whey protein isolate

Group 2- 40 g whey protein isolate

Participants:

Total= 30 healthy, resistance trained (>= 2 sessions/week for past 6 months) males divided into Group 1 (n=15) and Group 2 (n=15)

Methods:

Volunteers participated in two infusion trials (used to measure MPS response) after doing whole-body resistance exercise and ingesting whey protein isolate. Group 1 was given 20 g, and Group 2 was given 40 g whey protein isolate, immediately post-exercise.

Results:

Overall, Group 2 had greater MPS than Group 1, following whole-body resistance exercise.

Conclusion:

Based on this study, consuming more than 30 g high-quality protein following heavy resistance training is more beneficial for muscle growth. The level of resistance training and the type of exercises you perform may affect the amount of protein you can absorb.

 

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4985555/

Consuming More than 2.0 g/kg/d of protein when resistance trained impairs performance

This is a Myth!

Resistance Trained Individuals (resistance trained = weight training 2-3x/wk for at least past 6 mths) need higher levels of protein intake, but more has been proposed to be detrimental. It has been commonly accepted that 1.4-2.0g/kg/d (day) is sufficient.

But what about beyond 2.0g/kg/d?

2 major studies by Antonio et al. suggest otherwise:

Amount:

4.4g/kg/d & 3.4g/kg/d; both examining body composition.

Participants:

30 & 48 healthy resistance trained men and women.

Methods:

In the 4.4g/kg/d study groups were split into 1. Control Group & 2. High Protein Group for 8 weeks. Both groups were asked to maintain the same training and dietary habits (i.e. carbohydrates & fats). In the 3.4g/kg/d protocol similar groups emerged expect this time all participants completed a periodized split routine with heavy resistance.

Results:

1st study– NO adverse effects to a hypercaloric protein diet nor increase in body fat.

2nd study– NO adverse effects + the high protein group experienced higher decreases in fat mass & body fat %. Also the high protein group had greater performance gains in bench press, back squat, vertical jump, and pull-ups!

Conclusion:

Consuming a high protein diet in conjunction with a heavy resistance training program improves body composition and performance gains!

Excess Protein Raises Blood Glucose And Insulin Too Much

This is a myth!

Main takeaway 🔽

Adding protein that’s rich in leucine (meat) to meals, will help increase insulin secretion and stabilize your blood glucose levels after meals.

Eating carbohydrate-rich meals that are low in protein will give you higher blood sugar levels, with less insulin secretion, leading to more fat storage.

Excess protein will equate into more calories, and anytime you consume excess calories you will store fat, albeit, excess protein is associated with less excess calories as compared to fat and carbohydrates.

(For the nerds 🤓)
Nillson et al. (2018) showed there was a correlation of insulin responses after meals with early incremental consumption of amino acids and protein. The strongest correlations were shown for leucine, valine, lysine, and isoleucine. Milk powder and whey were shown to have substantially lower blood glucose increases as compared to cod, gluten-low & gluten-high meals, bread, and cheese. The highest blood sugar increase was shown thirty minutes after consumption of cod, bread, and gluten with an even more considerable decrease in blood sugar levels at minute sixty after consumption.

Reconstituted milk powder and whey had significantly lower glucose spikes but higher levels of insulin released; therefore, more of the sugar is absorbed and utilized by the cells. The meals containing bread, cod, and gluten were shown to have lower amounts of leucine, the highest increase in blood glucose levels, and a half or less the amount of insulin released.
Therefore, if more glucose is released and even more is unused by the cells, then excess glucose will then be stored as glycogen and also converted to fat in the liver.
Protein does increase insulin, but at different levels; food proteins differ in their ability to stimulate insulin release. It is thought to be because of the amino acid profile of the food. Leucine, Alanine, and Arginine (fuels used by the pancreas to make energy) are associated with a higher release of insulin. Milk proteins have insulinotropic properties containing the predominating insulin secretagogue. We see our most substantial increases in blood sugar levels in carbohydrate-rich meals.

Meals in the study that were higher in the amino acid leucine were shown to have more stable blood sugar levels. Isoleucine, Lysine, and Valine were also demonstrated in correlation to better insulin responses.

 

https://www.ncbi.nlm.nih.gov/pubmed/15531672

Higher Protein Intake is Hard On the Kidneys

This is a myth!

Higher protein (HP) diets (above RDA recommendations) have been used to promote weight loss, preserve muscle mass, and prevent sarcopenia. However, there is a myth that higher protein diets lead to kidney dysfunction. The indicator would be a change in glomerular filtration rate (GFR).

It turns out that the data does not support such a myth.

 

A meta-analysis conducted by Phillips et al. looked at higher protein diets (≥1.5 g/kg body weight or ≥20% energy intake or ≥100 g protein/d) and their effects on kidney function. When compared to normal- or lower-protein (NLP; ≥5% less energy intake from protein/d) diets, HP diets resulted in higher GFR overall; however HP intake did not influence changes in GFR. Thus, it was concluded that HP intake does not negatively influence renal function in healthy adults.

A systematic review of randomized control trials and epidemiologic studies conducted by Elswyk et al found that HP intake (≥20% but <35% of energy or ≥10% higher than a comparison intake) had little to no effect on blood markers of kidney function (i.e., blood pressure) when compared to groups following US RDA recommendations (0.8 g/kg or 10-15% of energy).

Coming from the PROT-AGE study group, “both endurance- and resistance-type exercises are recommended at individualized levels that are safe and tolerated, and higher protein intake (i.e., ≥ 1.2 g/kg body weight/d) is advised for those who are exercising and otherwise active. Most older adults who have acute or chronic diseases need even more dietary protein (i.e., ‪1.2-1.5‬ g/kg body weight/d).” However, individuals with severe kidney disease (GFR <30 mL/min/1.73 m(2)), but who are not on dialysis, are an exception to the rule; this cohort may need to limit protein intake.

Our goal is to optimize. According to Schoenfeld et al., reaching the minimum threshold of 1.6 g/kg spread out evenly throughout the day is necessary to maximize anabolism.

 

https://www.ncbi.nlm.nih.gov/pubmed/23867520

If you goal is to maximize muscle growth, it doesn’t matter when you eat your protein, as long as you eat it

This is a myth!

Always identify the goals you have and more importantly, the strategies you’ll employ to maximize results.

That’s right- it’s not only about the daily protein amount that matters. There is a protein threshold that is required for maximizing muscle protein synthesis (MPS). That per-meal threshold for MPS varies depending on age, sex, level of training, and whether or not you’ve trained that day.

Tipton et al reported that a 20g dose of whey protein is sufficient for maximal stimulation of myofibrillar MPS for both rested and exercised muscle of healthy young men (20-24 yr).

Similarly, Phillips et al reported that MPS reaches a maximal stimulation after ingestion of 20g high-quality protein post-resistance training in young healthy men (20-24 yr).

Phillips et al reported that for older men (73 +/- 2 yrs), ingestion of 35 g whey protein results in greater AA absorption and use for de novo MPS, compared with ingestion of 10 or 20 g whey protein.

Thus, frequent protein ingestion of sub-threshold protein amounts won’t stimulate the anabolic response.

In addition, one would need less protein consumption during resistance training days. Ingestion of 20g protein is sufficient to maximally stimulate MPS and APS (Albumin protein synthesis) post-resistance exercise.

This is because the two drivers of MPS (resistance training and protein ingestion) are essential for those looking to maximize building muscle.

     Overall daily protein consumption matters greatly of course; if you are a healthy adult, above 1.2 g/kg is optimal. But if you want to really maximize muscle growth, dialing in protein consumption timing may level you up.

 

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4985555/

High protein causes bone demineralization

This is a myth!

Protein does not cause osteoporosis nor declining bone health. In fact, the opposite is true. High quality dietary protein is necessary for strong bones.

 

Heaney & Layman (2008) examined that bone health depended on a variety of factors:

1) Level of protein in the diet

2) Protein source

3) Calcium intake

4) Weight loss

5) Acid/base balance of the diet.

The review also acknowledged a study of 191 subjects over 20 years that found protein intakes from 0.41 – 1.96 g/kg had no effect on calcium absorption efficiency. No differences in measured markers in the blood for bone turnover were found in either a high protein or high carbohydrate diet.

Studies have shown that various protein sources may exhibit different effects on bone metabolism. It has been shown that:

Animal Source = Higher serum levels of IGF-1

Soy foods/Products = Lower levels of IGF-1.

High levels of IGF-1 are related to bone growth. As individuals age, there are declines in serum levels of IGF-1 concentration.

Both the level of protein and the type of protein in your diet may have an effect of IGF-1 levels in the body.

What about Calcium Intake?

Protein intake increases urinary calcium loss, but whether there is a negative calcium balance, depends on dietary calcium intake.

Highest Protein Intake + Calcium/Vitamin D Supplementation = Positive Bone Health

Take Away Point

👇🏼👇🏼👇🏼

High levels of protein do not result in bone demineralization or a decrease in bone mass. High protein diets, rich in calcium help to increase bone mineralization and decrease the risk of fracture.

Source: https://www.ncbi.nlm.nih.gov/m/pubmed/18469289/