Protein is not insulinogenic

In other words, Protein has minimal effect on your Insulin levels (Donald K. Layman Jamie I. Baum. Dietary Protein Impact on Glycemic Control during Weight Loss. The Journal of Nutrition, Volume 134, Issue 4, 1 April 2004, Pages 968S–973S.):

These data suggest that amino acids have minimal impact on plasma insulin concentrations when entering the body via the GI tract.

There’s data which shows a large effect of protein on Insulin but that protein was mainlined into the veins of the test subjects. Unless you are injecting your protein, you’ve got nothing to fear from protein.

Most of these studies used direct intravenous infusion of amino acids into the human forearm under fasted conditions and used euglycemic clamp techniques to measure glucose uptake and insulin resistance. Using these techniques, investigators found that acute increases in plasma amino acid concentrations resulted in higher plasma glucose concentrations, lower glucose uptake, and elevated plasma insulin levels.

Here’s one experiment cited which makes that point:

One of the first studies of the differences in amino acid metabolism between i.v. administration and oral intake was by Floyd et al. (51,52). These investigators evaluated the insulin response to i.v. infusion of amino acids or glucose (51) and also examined the insulin response to oral intake of protein (52). They found that infusion of 30 g of amino acids produced a 3-fold higher insulin response (∼180 μU/mL) than infusion of 30 g of glucose (∼50 μU/mL), suggesting a dramatic hyperinsulinemic effect of amino acids.

However, these investigators also examined the same measurements after subjects consumed a meal of 500 g of beef liver and found that the peak insulin response to the protein meal was only 30 μU/mL. Assuming that leucine is 1 of the most potent insulin secretagogues, the i.v. infusion provided <5 g of leucine while the beef meal provide >14 g of leucine (52). These data suggest that amino acids have minimal impact on plasma insulin concentrations when entering the body via the GI tract.

BCAAs may be the exception since the reach the bloodstream directly like carbohydrates…

The primary exceptions to this pattern of modifications are the BCAA, with over 80% of dietary content of leucine, valine, and isoleucine directly reaching blood circulation.

I wonder if that’s part of their popularity as a supplement?

Speed has an effect too:

For glucose, the postprandial handling occurs mostly within the first 2 h (43); however for amino acids the rate of disposal is much slower with <20% of the dietary amino acids degraded within the first 2 h (48). Thus, direct comparison of a high carbohydrate diet vs. a high protein diet is that the carbohydrate diet requires rapid equilibration of the glucose and insulin metabolic system with dramatic shifts between hepatic vs. peripheral regulations, while a high protein diet serves to stabilize the glycemic environment with delayed metabolism and less reliance on peripheral insulin actions.

And most relevantly to this page:

…diets with reduced carbohydrates and higher protein stabilize glycemic control during weight loss

This part gets really interesting since it describes metabolically broken folks like us…

As expected, as the subjects lost weight (∼6.3 kg) during the 10-wk energy restriction and they improved glycemic control as measured by reduced postprandial insulin response to the test meal. For the CHO Group, average values at wk 0 = 77 μU/mL and at wk 10 = 38 μU/mL. On the other hand, subjects consuming the moderate protein diet achieved normal values for 2-h insulin response after only 4 wk on the diet with average values at wk 0 = 75 μU/mL and at wk 10 = 12 μU/mL. These changes appear to be beneficial associated with the overall risk patterns of obesity and Metabolic Syndrome (57,58).

In summary:

In summary, use of diets with higher protein and reduced carbohydrates appears to enhance weight loss with greater loss of body fat and reduced loss of lean body mass. Beneficial effects of high protein diets may be increased satiety, increased thermogenesis, sparing of muscle protein loss, and enhanced glycemic control. Specific mechanisms to explain each of the observed outcomes remain to be fully elucidated. We suggest that a key to understanding the relationship between dietary protein and carbohydrates is the relationship between the intakes of leucine and glucose. Leucine is now known to interact with the insulin-signaling pathway with apparent modulation of the downstream signal for control of protein synthesis resulting in maintenance of muscle protein during periods of restricted energy intake. Leucine also appears to modulate glucose use by skeletal muscle. While total protein is important in providing substrates for gluconeogenesis, leucine appears to regulate oxidative use of glucose by skeletal muscle through stimulation of glucose recycling via the glucose-alanine cycle. These mechanisms appear to provide a stable glucose environment with low insulin responses during energy-restricted periods.

 

 

Exercise and Blood Sugar Control

Here’s a meta-analysis that looked at the effect of exercise and blood sugar control in diabetics (Neil J. Snowling, MSC and Will G. Hopkins, PHD. Effects of Different Modes of Exercise Training on Glucose Control and Risk Factors for Complications in Type 2 Diabetic Patients: A meta-analysis. (PDF) Diabetes Care 2006 Nov; 29(11): 2518-2527.) which concluded:

Differences among the effects of aerobic, resistance, and combined training on HbA1c (A1C) were trivial; for training lasting ≥12 weeks, the overall effect was a small beneficial reduction (A1C 0.8 ± 0.3% [mean ± 90% confidence limit]).

There were generally small to moderate benefits for other measures of glucose control.

For other risk factors, there were either small benefits or effects were trivial or unclear, although combined training was generally superior to aerobic and resistance training.

Effects of covariates were generally trivial or unclear, but there were small additional benefits of exercise on glucose control with increased disease severity.

The Low Carb diet has a much more significant effect than exercise. But are there any studies showing the power of the Low Carb diet compared with exercise?

 

Athlete’s Blood Sugar Study – Part 2

In my post (Looking Closer at the Athlete’s Blood Sugar Study) I took a quick look at this study (Felicity Thomas, BE(Hons), Chris G. Pretty, PhD, Thomas Desaive, PhD, and J. Geoffrey Chase, PhD. Blood Glucose Levels of Subelite Athletes During 6 Days of Free Living. J Diabetes Sci Technol. 2016 Oct; 10(6): 1335–1343.)

Let’s do a deeper dive on the data and see what trends we can detect. Fortunately, at least some of the data was published:

BMI vs Fasting Blood Sugars

First, let’s test the question of the correspondence of Fasting Blood Sugar levels and BMI.

There was a linear association between the Fasting Blood Glucose (FGB) and Body Mass Index (BMI). The R^2 was small, at 0.12. The BMI range of these individuals was also less than a typical population since they were athletes.

Reference: Regression Analysis: How Do I Interpret R-squared and Assess the Goodness-of-Fit?

Fasting Blood Sugar vs Body Fat Percentage

Looking at Body Fat Percentage vs Fasting Blood Sugar shows a similar correlation to BMI. The R^2 value of 0.15was similar to the BMI value.

Fat Free Mass vs Fasting Blood Sugar

So does having a larger fat free mass help with fasting blood sugars?

Unfortunately this goes the wrong way. Rather than leading to a lower blood sugar more fat free mass leads to higher blood sugar but with the same R^2 number of 0.14.

Fasting Blood Sugar vs Fasting Insulin Secretion

There is a negative correlation between Fasting Blood Sugar and Fasting Insulin Secretion.

This is also a weak correlation with an R^2 of 0.056. Although the individuals had higher fasting blood sugars they also produced less insulin in the fasted condition.

Fasting Blood Sugar vs Post-prandial Insulin

Fasting blood sugar showed the largest correlation to post-prandial Insulin levels with an R^2 of 0.56. Individuals with poorer blood sugar control produced more insulin than others.

Fasting Blood Sugar vs Age

Although age is often viewed as central to a loss of control of blood sugar, in this group the association was not present in this data set.

Exercise Amount per Day vs VO2max

I’ve often wondered how well the amount of time a person exercises each day affected their VO2max number. There’s a small positive correlation between the two. The R^2 was only 0.11.

Fasting Blood Glucose vs Glucose Time in Band

Glucose Time in Band was the percentage of the time that blood sugars were within the “good” range.

There was a relatively strong negative correlation between the time fasting blood glucose and the Glucose Time in band. The R^2 value was 0.74.

This leads me to conclude that fasting blood sugar numbers were a good indicator of the glucose time in band.

Looking Closer at the Athlete’s Blood Sugar Study

In Heart Rate Training – Part 9, I took a look at a really interesting 2016 study on Blood Sugar levels in athletes (Felicity Thomas, BE(Hons), Chris G. Pretty, PhD, Thomas Desaive, PhD, and J. Geoffrey Chase, PhD. Blood Glucose Levels of Subelite Athletes During 6 Days of Free Living. J Diabetes Sci Technol. 2016 Oct; 10(6): 1335–1343).

The study looked at ten athletes and their blood sugars. They discovered that four of the ten athletes were pre-diabetic. Let’s take a look and see what additional information we can tease from the data.

The study had three females and seven males.

All but 4 participants consumed on average an amount of carbohydrate that was between 45 and 65% of their recommended daily calorie intake.

Ath05, Ath07 and Ath09 have elevated fasting glucose within the prediabetes range 5.6-6.9 mmol/L suggested by the ADA.

The mean PPGR ranges from 0.2 to 2.0 mmol/L.hr displaying a wide range intra and inter of carbohydrate sensitivity.

Fortunately, they included some of the data on the participants.

Subject Sex Age BMI PBF (%) FFM (kg) FBG (mmol/L) FPI (mU/L) FIS (mU/L.min) TIB-MR (%) Mean PPGR (mmol/L.hr) Mean PPG (mmol/L) Exercise (min/day) VO2max (mL/kg/min)
Ath01 F 23 21.6 25.3 45 5.2 9 1319 86.6 1.1 6.1 84 39
Ath02 M 23 21.9 5.1 6.3 913 90.7 0.5 6 41 60
Ath03 M 50 26.4 4.7 11.8 1878 76.1 1.9 6 68 39
Ath04 M 23 20.4 5.1 64.8 4.6 6.5 832 99.2 0.5 5.5 93 67
Ath05 M 28 24.2 14.1 60.6 6 6.3 820 30.7 0.9 6.8 158 59
Ath06 M 36 22.4 15.5 63.3 4.4 8.3 1844 94.3 1.2 5.9 28 59
Ath07 M 37 26 19.7 65.3 6.7 10.5 1553 23.9 1.1 7.1 20 42
Ath08 M 22 24.5 13.2 70.6 5.5 11 1550 31.7 0.2 5.5 24 37
Ath09 F 37 21.1 17.8 46.7 6 6 936 9.7 2 7.4 102 47
Ath10 F 27 22.2 28.3 47.7 5.2 9.5 1344 86.6 1 6.7 42 44
  • FBG, fasting blood glucose;
  • FFM, fat free mass;
  • FIS, fasting insulin secretion;
  • FPI, fasting plasma insulin;
  • Maxppg, maximum blood glucose value reached after a meal; PBF, percentage body fat;
  • PPG, blood glucose value 2 hours after a meal;
  • PPGR, postprandial glucose response;
  • TIB-MR, time in band, with meals removed.
  • Body composition analysis results were not available for Ath02 and Ath03, hence PBF and FFM values are missing.

Ath03 – Unique Case

Let’s focus in on Ath03. This athlete is a 50-yr old male who has a good fasting glucose number at the same time as a high fasting Plasma Insulin and high fasting Insulin Secretion number. As the paper states:

A subject can achieve good overall control or even experience low BG, such as Ath03, but still demonstrate a high mean PPGR indicating a high sensitivity to carbohydrates.

Here is a really interesting note:

Ath03 consumed on average ~150 g of carbohydrate less than the lower recommended limit, 1770 kcal less than required (Table 2) and was the only participant to demonstrate a significant amount time below 4.0 mmol/L.

The study stated:

Athletes are traditionally encouraged to consume high carbohydrate diets to replenish muscle glycogen stores and improve performance, with a particular focus on postexercise carbohydrate consumption. However, this advice may be negatively impacting the blood sugar levels of athletes predisposed to have a low tolerance of carbohydrates.

This is exactly my concern. Are weekend warriors fueling themselves as if they are elite athletes and suffering metabolic damage as a result?

 

Turmeric and Curcumin for Osteoarthritis and Joint Pain

Here’s a meta-analysis of the use of Turmeric and Curcumin for Osteoarthritis and Joint Pain (Daily James W. , Yang Mini , and Park Sunmin. Efficacy of Turmeric Extracts and Curcumin for Alleviating the Symptoms of Joint Arthritis: A Systematic Review and Meta-Analysis of Randomized Clinical Trials. Journal of Medicinal FoodVol. 19, No. 8.). The study

systemically evaluated all RCTs of turmeric extracts and curcumin for treating arthritis symptoms to elucidate the efficacy of curcuma for alleviating the symptoms of arthritis.

The conclusions were

…meta-analysis of four studies showed a decrease of WOMAC with turmeric/curcumin treatment (mean difference: −15.36 [−26.9, −3.77]; P = .009). Furthermore, there was no significant mean difference in PVAS between turmeric/curcumin and pain medicine in meta-analysis of five studies.

…these RCTs provide scientific evidence that supports the efficacy of turmeric extract (about 1000 mg/day of curcumin) in the treatment of arthritis. However, the total number of RCTs included in the analysis, the total sample size, and the methodological quality of the primary studies were not sufficient to draw definitive conclusions. Thus, more rigorous and larger studies are needed to confirm the therapeutic efficacy of turmeric for arthritis.

I haven’t found any other solution to my shoulder pain and I refuse to use NSAIDs or pain medications so I am trying Turmeric Curcumin.

 

Ketones and Blood Sugar Responses to Exercise

Background

Determine the effects of exercise on blood glucose and ketone levels.

The prediction prior to exercise was that blood glucose levels would increase and ketone levels would decrease immediately following exercise but would rebound to a blood glucose level that was lower than the baseline and ketone levels would increase to a level higher than the baseline within a couple of hours.

Methods

The subject of this study is a male, 58-year old, approx 75 kg in weight who has been doing CrossFit training for about 10 months. Subject eats a ketogenic diet (less than 30 grams of carbohydrates per day). Subject was fasted overnight (about 14 hours) and exercise was performed in the morning. Subject had one cup of coffee with salt (Morton Lite Salt plus Sea Salt) added prior to exercise and one cup of same post-exercise. Exercise routine consisted of warmup followed by relatively high intensity workout. The warmup consisted of calisthenics and a 400 M run taking a total of about 8 minutes. The intense portion of the workout took about 16 minutes. Heart rate was recorded using a Samsung Gear Sport heart monitoring watch. Blood sugar was measured using a Livongo Blood Glucose Meter. Ketone Levels were measured using a Keto Mojo Blood Ketone meter.

Results

Blood Ketone levels were 1.0 at the start of the exercise, fell to 0.3 at the end of the exercise, 0.4 at 1 hour post exercise and 1.5 at 2 hours post exercise. Initial ketone level indicates subject was fasted and was in nutritional ketosis. Blood Sugar levels were 92 at the start of the exercise, 129 at the end of the exercise, 82 at 1 hour post exercise and 89 at 2 hours post exercise. Subject’s heart rate reached a maximum of 188 beats per minute and was noted to be at maximum for 15 minutes, vigorous for 7 minutes and moderate for 9 minutes.

Conclusions

Intense exercise results in an increase in Blood Glucose levels which fall to lower than baseline level within in an hour. Intense exercise also results in a decrease in measured ketone levels in the blood. These reactions could cause psychological distress to someone who sees them for the first time in themselves but are common reactions to intense exercise.


The Intense Workout

The intense portion of the workout consisted of Medicine ball Cleans using a 14-pound medicine ball and Strict Chest To Bar pullups using resistance bands. The progression was as follows:

The time to complete the intense portion was:

Data – Chart

Time   Note Blood Sugar Ketone Level
-45 mins Start of exercise 92 1.0
0 mins End of exercise 129 0.3
60 mins Post-exercise 82 0.4
120 mins Post-exercise 89 1.5

Heart Rate Data

Additional Watch Data was:

Cortisone Injections in Diabetics

I had a cortisone shot in my shoulder for pain yesterday.

Today my blood sugar is up into the mid 130’s. That’s high for me but no where near what it used to be when I had this shot years ago. My blood sugar used to go into the low 200’s then.

I do remember that the effect lasts a few days. The science shows this is the case (The Journal of Hand Surgery. July 2006, Volume 31, Issue 6, Pages 979–981. The Effect of Corticosteroid Injection for Trigger Finger on Blood Glucose Level in Diabetic Patients. Angela A. Wang, MD, et.al.).

The blood glucose level increased after corticosteroid injection for all patients. The first morning after injection showed the biggest increase in blood glucose level: 73% more than the average preinjection levels. By the fifth morning after injection the blood glucose levels still were increased by 26% more than the preinjection levels. This trend was marked particularly in type I diabetic patients, who had an average blood glucose level increase the first morning after injection of 145%, which decreased over 5 days to 22% greater than baseline levels.

A second study showed a significant mean increase over the next few days after the shot (J Hand Surg Am. 2014 Apr; 39(4): 706–712. Blood glucose levels in diabetic patients following corticosteroid injections into the hand and wrist. Jeffrey G. Stepan, et.al.):

I wonder if this relates to increased blood sugar secretion or an insulin resistant reaction? This site indicates that they cause temporary insulin resistance (Corticosteroids and Diabetes).

One of the side effects of oral corticosteroids is that they can increase blood glucose levels and increase insulin resistance, which can lead to type 2 diabetes.

Typically, blood glucose levels will return to normal after you finish taking the steroids but in some cases, particularly if you have pre-existing risk factors for type 2 diabetes, you may be diagnosed with this form of diabetes.

Types of Exercise and Glycogen

I have been trying to tease out the limits of low carb performance. Here is a key paper (Metabolism. 1983 Aug;32(8):769-76. The human metabolic response to chronic ketosis without caloric restriction: preservation of submaximal exercise capability with reduced carbohydrate oxidation. Phinney SD, Bistrian BR, Evans WJ, Gervino E, Blackburn GL).  Buried within the paper is:

In agreement with this were a three-fold drop in glucose oxidation (from 15.1 to 5.1 mg/kg/min, P less than 0.05) and a four-fold reduction in muscle glycogen use (0.61 to 0.13 mmol/kg/min, P less than 0.01).

This seems buried because of the units used. Another site (September 13, 2017. Why Am I Getting Low Ketone Readings on a Ketogenic Diet? By Mark Sisson) translates these units as:

During the high-carb arm, the group began the workout with 150 grams of glycogen and ended it with 50 grams. While eating ketogenic, the group began the workout with 75 grams and also ended it with 50 grams.

The time of this test was approx 150 minutes.

 

Carbs After Workouts?

If you are exercising to improve your insulin sensitivity, then Carbs after workouts are bad. Here’s the science (Nutrients. 2018 Jan 25;10(2). pii: E123. PostExercise CarbohydrateEnergy Replacement Attenuates Insulin Sensitivity and Glucose Tolerance the Following Morning in Healthy Adults. Taylor HL, Wu CL, Chen YC, Wang PG, Gonzalez JT, Betts JA.)

In this study they put participants on a 90-minute treadmill at 70% of their VO2max. At the end they gave the participants either a placebo (no carbs) or maltodextrose that matched the caloric expenditure. Researchers then measured the glucose and insulin responses with an Oral Glucose Tolerance Test (OGTT) the following day and found that the participants who had the carbohydrates had reduced Insulin Sensitivity and increased blood glucose levels.

The practical conclusion of this is that to maximize Insulin Sensitivity it is best to both eat low carb and take no carbs after exercise. Decreased Insulin Sensitivity is one of the markers that lead to Diabetes and increasing Insulin Sensitivity is an important part of reversing Diabetes.

This study is the first to show that feeding carbohydrate to replace that utilized during exercise can reduce insulin sensitivity and glucose tolerance the next morning in healthy adults, when compared to a preservation of the exercise-induced carbohydrate deficit. Furthermore, carbohydrate replacement suppresses subsequent postprandial fat utilization. The mechanism through which exercise improves insulin sensitivity and glucose control is therefore (at least partly) dependent on carbohydrate
availability, and so the day-to-day metabolic health benefits of exercise might be best attained by maintaining a carbohydrate deficit overnight.

For those people who are not particularly concerned about their risk of getting Diabetes it’s worth noting that if they refill their Glycogen stores quickly with carbohydrates they are not burning fat. If they let the Glycogen stores be low then their body will burn fat.

Want to burn fat? Work out and don’t eat carbohydrates after working out.

Here’s a second study on the effects of post-workout carbs (Journal of the International Society of Sports Nutrition 201512:48. The effects of whey protein with or without carbohydrates on resistance training adaptations. Juha J. Hulmi, Mia Laakso, Antti A. Mero, Keijo Häkkinen, Juha P. Ahtiainen and Heikki Peltonen.) This study carefully compared three post-workout nutritions:

  • Whey Protein Alone
  • Carbohydrate Alone
  • Whey Protein plus carbohydrates

All three groups in this study had gains in strength from the resistance training (RT). However, only the Whey Protein Alone had a decrease in fat mass. The study concluded:

Conclusions

This first long-term study supports the acute protein balance studies showing that adding carbohydrates to postexercise protein ingestion may not have large effect on the RT adaptations.

Whey proteins, however, increased abdominal fat loss and relative fat-free mass adaptations in response to resistance training when compared to fast-acting carbohydrates.

Therefore, if the main goal is to maximize fat loss responses to RT especially from abdominal area without compromising increases in muscle hypertrophy, whey protein instead of carbohydrates can be recommended for the postexercise nutrition.

Bottom line is that if you want to get leaner from resistance training, don’t eat carbs post-workout.