Information on sport supplementation for people with Diabetes is divided, it is difficult territory with many either not wanting to make an out and out verdict, or because information out there is conflicting or not supported by peer reviewed articles. Some say the consumption of a whey protein is fine whilst others argue otherwise, but either way, supplementation should never be considered in isolation. As most Diabetics will know, diet is probably the single most important factor in blood sugar control meaning the insulinogenic effect of whey protein is only one factor to consider when taking such products. It is reasonably well documented that serum (blood) levels of leucine, isoleucine, valine, lysine and threonine increase after the consumption of whey protein; as a result, our bodies (unless you’re Type 1 diabetic) produce more insulin to allow for absorption into the muscles and organs.
Amino Acid Response in Humans after Consuming Whey Protein
(Salehi, Gunnerud, Muhammed, et al. 2012)
Amino acid levels (triangles on chart) peak at around 45mins after the consumption of whey protein but gradually climb after 10-15mins, compared to white wheat bread (WWB) (squares on the chart) which causes an amino acid drop almost immediately after ingestion. Incidentally, it was concluded that only leucine caused a significant increase in insulin relative to that of glucose alone, but interestingly when all amino acids were consumed in a shake, the insulin response was greater than that of glucose alone!
Insulin Response after Consuming Whey Protein/Amino Acid
(Salehi, Gunnerud, Muhammed, et al. 2012)
The above chart shows the insulin release relative to each individual amino acid and when the amino’s were combined together and mixed with glucose-dependent insulinotropic polypeptide (GIP), a hormone that looks after the insulin response after glucose consumption. It is clear from the above graph that amino acids actually exert as much of an insulin response as glucose alone, demonstrating the importance of monitoring blood sugar and insulin levels when consuming whey protein (Salehi, Gunnerud, Muhammed, et al. 2012).
NHS Choices (2012) state that starchy carbs such as pasta, rice (particularly brown or basmati rice), wholegrain bread, cereals, potato, noodles and chapattis are vital to delivering a slow, drip like flow of carbohydrate to your body’s tissue (muscle and organs) as a source of energy. In order to prevent the undesirable peaks and troughs (ups and downs) associated with Diabetes, three regular meals should be consumed every day including breakfast, lunch and evening meal. In between meals one should aim to have another starchy carb such as one or two rice cakes or ryvitas, ideally never going longer than 2-3 hours without eating, including a starchy carb.
Is sugar, sugar? Well, to all intents and purposes yes, only some are derived from fruit (fructose), animal sources (lactose), and others are from roots such as sugar beet and canes/grasses (sucrose). No matter where the sugar is derived, it will have an effect on blood sugar so it is very important that sugar is consumed with other foods to reduce the rate of digestion and absorption into the blood stream. Hence it is wise to avoid having a high sugar foodstuff i.e. anything above 10g of sugar per 100g serving, too often and on an empty stomach or without following it with food. This rule holds true with protein shakes too!
Protein Shakes and Blood Sugar
The general concern for those people with Diabetes and Impaired Glucose Tolerance is not so much the direct impact protein shakes have on spiking blood sugar levels, but more so the insulin response the liquid protein, fat and carbs have on insulin! Diabetic or not, whenever we consume a protein shake our pancreas produces insulin (provided you’re not a Type 1 diabetic) in order to unlock the muscles and organs to enable the amino acids and carbs to enter. Type 1 diabetics are not able to make their own insulin meaning they have to inject insulin, and type 2 diabetics either have difficulty producing insulin and/or become less receptive to insulin’s effects i.e. insulin no longer unlocks the muscle for carbs and protein. The problem with this is that if your body is unable to unlock the muscle, you end up with a back log of amino acids and sugar in your blood meaning you get that dreaded ‘blood sugar spike’. The thing is this, it is not really the spike that is the problem, in reality it is the erratic compensatory drop in blood sugar that follows maybe 15-20mins after the insulin release which causes most of the sugar/glucose in the blood to enter the muscle and bodily tissue. Consequently the level of sugar in the blood drops meaning hypoglycaemia (low blood sugar) is a real risk (Mayo Clinic, 2012).
Stabilise Blood Sugars
In order to prevent/limit the insulin spike and resultant drop in blood sugar that follows, try to consume starchy carbs on a regular basis i.e. consuming a few rice cakes with cottage cheese around 40mins before exercise. Also try to avoid a single load of sugar and amino acids (found in a protein shake) without following it up with a starch, protein and healthy fat source after. The addition of fibre to a protein shake can also slow the rate of absorption, minimising the sudden spike in insulin that follows a protein shake.
Many people claim that their protein shake does not affect their blood sugar levels at all, but it is always worth checking your reading on a regular basis, especially when you first start out! Do remember that what you have eaten earlier on in the day will affect your blood sugar and insulin response. Therefore do not take your blood sugar reading after whey protein as a set rule because many factors such as illness, stress, fatigue and dietary intake can also impact on your readings.
Low Carb Whey Protein
Reflex Nutrition Micro Whey (0.6g Carbohydrate per 30g scoop of which 0.6g is sugar)
USN Pure Protein GF-1 (1.1g Carbohydrate per 30g scoop of which 0.6g is sugar)
Optimum Nutrition 100% Gold Standard Whey (4g per 30g scoop of which 1g is sugar)
This article is not a comprehensive discussion on Diabetes and Supplementation, anything written is based on the consensus drawn from current, peer reviewed research and is not a categorical declaration of best practice. Please always speak with your Doctor or Registered Dietitian or Diabetes Specialist Nurse should you have specific concerns or questions.
NHS Choices, Your Health, Your Choices, (2012). Healthy Living with Diabetes. Retrieved 7th Feb, 2013, from http://www.nhs.uk/livewell/diabetes/pages/healthfordiabetics.aspx
Mayo clinic, (2012). Whey Protein. Retrieved 7th Feb, 2013, from discount supplements
Salehi, A., Gunnerud, U., Muhammed, S, J., Ostman, E., Holst, J, J., Bjorck, I, & Rorsman, P. (2012). The insulinogenic effect of whey protein is partially mediated by a direct effect of amino acids and GIP on β-cells. Nutrition & Metabolism. 9:48