Dextrose is a simple sugar (specifically a monosaccharide) and is identical in chemical structure to glucose. The term “dextrose” simply refers to glucose derived from corn. Glucose is the most fundamental sugar, made up of one monomer (sugar unit) and serving as an energy source for many life forms. When you consume carbohydrates, your body breaks them down into separate glucose molecules so that they can be transported to cells for energy (ATP) production.
Hence, many avid gym-goers and athletes use dextrose for bodybuilding purposes since it rapidly increases insulin levels (i.e. it is a high-glycemic carbohydrate source), which in turn helps shuttle amino acids and other muscle-building nutrients into skeletal muscle tissue after intense training.
Moreover, dextrose is often used in medical settings to treat hypoglycemia or malnutrition (in such instances, it may be given intravenously). Since dextrose is derived from corn and has a long shelf-life, you can find this simple sugar in many sweetened, packaged foods (especially candy).
There’s much more to consider pertaining to the use of dextrose for bodybuilding, so read on as we take a deep dive into this type of sugar.
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Dextrose for Bodybuilding
Chances are you’ve picked up more than one bodybuilding or fitness magazine and read that you need to replenish your muscle glycogen and spike insulin levels as soon as possible after you’re done training (specifically after lifting weights).
So, what’s the best way to accomplish this goal?
Arguably, it’s dextrose. Since dextrose is identical to glucose, your body doesn’t need to enzymatically break it down as it does with other carbohydrates. This means that your blood sugar levels will increase rapidly after consuming pure dextrose, as will your insulin.
When you consume complex carbohydrates, like those found in oats, your body slowly breaks them down into glucose molecules over time, creating a slower, sustained rise in blood sugar levels and milder increase in insulin secretion. While complex carbohydrates are great during certain times of the day, they aren’t ideal immediately after exercise (and they may not even be ideal immediately before training either).
Why is that, you ask?.
Since insulin is a highly anabolic hormone that helps restore muscle glycogen and increases muscle protein synthesis when consumed in conjunction with protein/amino acids, the use of dextrose for bodybuilding is quite prudent.
After you finish an intense weight training session, your muscles are usually depleted of muscle glycogen and become more sensitive to the effects of insulin. In other words, the muscle you just trained is eager to soak up glucose and amino acids so they can repair and grow (hypertrophy), and insulin helps them do just that.
What is Dextrose? How Does it Affect My Bulking?
To reiterate, dextrose is simply glucose that comes from corn. Glucose is a simple sugar (monosaccharide) that our body uses to produce energy/ATP. Since dextrose is chemically identical to glucose, it is rapidly absorbed and creates a sharp increase in blood glucose and insulin levels.
Dextrose can be great for bulking when it’s used in a proper fashion since it helps shuttle key nutrients into muscle cells, thereby helping them rebuild and grow. However, it’s vital to keep in mind that consuming excessive amounts of any nutrient is not ideal, even if you are trying to bulk up.
Dextrose is essentially an empty-calorie nutrient since it doesn’t provide any micronutrient value. It’s great for increasing insulin and blood sugar, which is useful after lifting weights; beyond that, it doesn’t have much value.
What about Lean Muscle Mass?
While dextrose for bodybuilding is beneficial in some ways, there’s a limit to how much your body can utilize for building lean mass at any given time. Remember, sugar (carbs) contain four calories per gram. If you’re slamming a shake with 100 g of dextrose after training, that’s a quick 400 calories (not including any protein or fat you might add to it).
Also keep in mind that insulin is a storage hormone and having chronically elevated insulin levels can lead to excessive fat gain, especially if you’re in an energetic surplus.
As such, it’s best to use moderate amounts of dextrose for bodybuilding, particularly after lifting weights in conjunction with a fast-acting source of whey protein.
However, dextrose should not be your main source of carbohydrates for building lean muscle mass. You’re better off consuming complex carbohydrates at other times of the day, such as the carb sources in Leftovers.
What if I’m Endurance Training?
For endurance athletes like marathoners, swimmers, and cyclists, dextrose can be a useful source of energy immediately before, during, and after an event, especially if it’s a long distance. In fact, this is why things like Gatorade and Powerade are so popular among athletes since they are a simple mixture of dextrose and electrolytes.
It’s important not to overdo it on dextrose though, even if you’re an endurance athlete. Consuming exorbitant amounts of sugar right before or during an athletic event can cause stomach aches, hyperglycemia (or hypoglycemia if your body secretes too much insulin), and sharp energy swings.
For most endurance athletes, it’s more ideal to consume long-lasting forms of energy a few hours before an event, such as complex carbohydrates or even exogenous ketones. Dextrose should only be used as a last-minute energy boost if you haven’t already fueled up in the hours leading to your event/training; you may also use dextrose during/after endurance exercise to help refuel, but you won’t need much; 20-30 grams should suffice for most people.
How Much Dextrose Should I Consume?
The answer to this question is highly relative based on what your immediate goals are and a myriad of other factors, such as your body weight, insulin sensitivity, muscle fiber type composition, and others.
If you’re using dextrose for bodybuilding and trying to pack on lean muscle mass, then a good starting point for most people is one gram of dextrose per kilogram of body weight consumed post-training with at least 25 g of whey protein.
For example, if you weigh 100 kg (220 lbs), consume a shake with about 100 g of dextrose and 30-40 g of whey protein after you finish destroying some weights. That’s more than enough to help maximize muscle protein synthesis and boost insulin levels sufficiently.
Also, be sure to monitor how you feel after you ingest a large amount of dextrose. Per example, If you find that 100 g at once makes you feel light headed and lethargic, chances are you should reduce the amount a bit next time around.
Moreover, you should feel hungry about 60-90 minutes after consuming a post-workout shake with whey protein and dextrose, since these nutrients are rapidly absorbed and won’t increase satiety much at all (especially after a hard training session).
Should I Consume Dextrose for Bodybuilding while Trying to Lose Fat?
For the vast majority of gym-goers, dextrose is not necessary while fat loss is the main goal. While insulin is a great hormone for protecting lean muscle mass from catabolism, it also directly antagonizes fat burning pathways in the body. You could still include a small amount of dextrose (20-30 grams) in your post-workout whey protein shake so long as you keep your total calorie intake low enough for fat loss.
What would be more prudent for fat loss is to supplement with branched-chain amino acids (BCAAs) before, during, and/or after training in lieu of dextrose. The insulin response from BCAAs is physiologically distinct from the insulin response you experience after consuming dextrose, and it won’t significantly alter fat burning during exercise. The great thing about BCAAs for fat loss is that they help protect your hard-earned muscle tissue without adding a ton of calories to your diet.
Can I Consume Dextrose on Keto?
If you’re on a traditional ketogenic diet, then dextrose is not recommended as it will quickly take you out of ketosis. However, there are definite instances when you could implement dextrose on the keto diet, particularly if you’re on the targeted ketogenic diet (TKD) or cyclical ketogenic diet (CKD) which allow you to strategically “refeed” with carbohydrates.
Nevertheless, one of the utmost goals of the keto diet is to keep insulin levels low, and dextrose completely antagonizes that. Your best bet if you’re on the CKD or TKD is to refeed with complex carbohydrates (especially those that have a low glycemic index, like oats, beans, sweet potato, etc.).
Medical Uses of Dextrose
In clinical settings, dextrose is often used to treat dehydration or low blood sugar (hypoglycemia). In these instances, a doctor may prescribe an IV solution containing dextrose, amino acids, and possibly fats. Symptoms of low blood sugar often include delirium, rapid heartbeat, weakness, shivering, and sweating. A simple remedy for most cases of hypoglycemia is to consume dextrose tablets or gel (which you can find over-the-counter at pretty much any pharmacy).
For those with hyperkalemia (high potassium levels), dextrose injections may be used in conjunction with intravenous insulin. The insulin helps reduce potassium levels while dextrose prevents the individual from experiencing hypoglycemia from the insulin.
Dextrose Side Effects
If you’re using dextrose for bodybuilding, you should be wary of certain side effects and symptoms. Paying attention to how your body responds after consuming dextrose is the best way to determine if you are a good candidate for regular use of dextrose.
Remember, nutrition is not all black and white and there is no one-size-fits-all diet or supplement protocol that works optimally for everyone. Some people will tolerate dextrose better than others, and this is just the nature of our biology. With that in mind, don’t be discouraged if you’re not getting the same results as your fellow gym bros who extol the benefits of slamming dextrose by the kilo after every workout.
The reality is that you can significantly increase muscle protein synthesis with just whey protein after training, and dextrose isn’t a true necessity for building lean muscle mass.
Now, about those dextrose side effects. The two most common side effects of dextrose are hyperglycemia and hypoglycemia paired with hyperinsulinemia. Interestingly, these can both be caused by consuming too much dextrose at once, and you’re more likely to face these side effects if you’re type-I diabetic/pre-diabetic/insulin resistant or if your body doesn’t have high insulin sensitivity to begin with.
Symptoms of hyperglycemia (elevated blood sugar) generally include:
● Increased thirst
● Trouble concentrating
● Blurred vision
● Frequent peeing
Clinically speaking, hyperglycemia means you have a blood sugar reading greater than 180 mg/dL. If you really want, you can purchase a blood glucose meter at a pharmacy and test your levels with a simple finger prick. This is especially useful if you’re using dextrose for bodybuilding and want a tangible idea of how your body responds to a large dose of sugar after training.
Symptoms of hypoglycemia/hyperinsulinemia typically include:
● Rapid heartbeat
Hypoglycemia is considered a blood sugar reading below 60 mg/dL. If your body secretes an excessive amount of insulin after you consume a bolus of dextrose, then you may be prone to hypoglycemia (symptoms will typically set in around 30-45 minutes after the fact).
In exceptionally rare circumstances, dextrose use may cause insulin shock (although this is really only plausible if you inject additional insulin while you’re in a hypoglycemic state). Nevertheless, if you’re a type-1 Diabetic that regularly uses insulin, then insulin shock (also known as Diabetic shock) is a real threat and not something you should take lightly as it can be fatal.
There are some people who should not use dextrose for bodybuilding or other purposes. Contraindications for dextrose use include:
● Corn allergies
● Hypokalemia (low blood potassium)
● Type-2 diabetes
● Individuals with peripheral or pulmonary edema
If you’re ever in doubt about using dextrose, be sure to consult with a registered dietitian and/or your primary doctor. They will be able to order the necessary assays to ensure you can safely use dextrose as part of your healthy lifestyle.
Where to Buy Dextrose Online or Offline
Where to buy dextrose for bodybuilding or other purposes? Believe it or not, dextrose is readily available at pretty much any supermarket or pharmacy you can find since it’s a very common form of sugar found in tons of foods and beverages. You can also find pure dextrose in most grocery stores (and many health/supplement websites).
Buying Dextrose Offline
Dextrose is simply the scientific name for corn sugar. Take a quick walk around your local grocery store or pharmacy, and you’ll find plenty of items made with corn sugar, particularly candy and soda. If you want just pure dextrose, then look for a bag of corn sugar, which is generally found in the baking aisle of the supermarket. It’s very cheap and will last a good amount of time even if you’re consuming 100 g per day (which is more than most people will need).
Depending on where you live and shop, a 10 lb bag of dextrose (corn sugar) will run around $20. Since there’s 454 g in one pound, that comes out to 4540 g of dextrose in a 10 lb bag, meaning you get about 45 100-gram doses for $20. Not a bad deal at all.
In some cases, having dextrose tablets or gels can be beneficial, especially if you’re a type-I Diabetic that regularly uses insulin. These are handy forms of dextrose that you can carry around in your pocket/purse/handbag/etc. in the event your blood sugar drops too low. Most pharmacies carry dextrose tablets and gels, as well as blood glucose meters if you need a reliable way to test your levels throughout the day.
Buying Dextrose Online
Like with everything these days, dextrose supplements are available all over the Internet. In reality, dextrose isn’t a supplement in the same sense as things like BCAAs and exogenous ketones.
Again, dextrose is just corn sugar and you can find it pretty much anywhere these days. It’s a food ingredient and not a supplement per se. Nevertheless, many supplement companies market dextrose like a “performance-enhancing” agent just to increase the cost and perceived value of their product(s). Don’t be fooled by this, though. You shouldn’t be paying much more than $2 per pound of dextrose powder whether it’s online or offline.
Dextrose for Bodybuilding: Key Takeaways
● Dextrose is a monosaccharide derived from corn that is identical in chemical structure to glucose.
● Bodybuilders and athletes commonly use dextrose after lifting weights to increase insulin levels and replenish muscle glycogen, which is conducive to muscle building.
● For bulking and building lean muscle mass, it’s best to consume a post-workout shake with around one gram of dextrose per kilogram that you weigh in conjunction with 25+ grams of whey protein.
● For fat loss, reduce or eliminate the use of dextrose. Opt for BCAAs instead.
● Common side effects of dextrose include hypoglycemia and hyperglycemia. It’s recommended to monitor your blood glucose levels if you experience either of these after consuming dextrose.
● You can buy pure dextrose (corn sugar) powder online and offline, but don’t be fooled by supplement companies that put a premium on their “carb supplements” that are simply flavored corn sugar. You should be able to buy dextrose powder for around $2 per pound; any more than that is a ripoff.
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