What Happens When You Consume Carbs?
Carb Cycling Meal Plans Should Be Personalized
Getting Started with a Smarter Carb Cycling Plan
Carbohydrates are essential to our body, especially as our primary source of energy, and they influence everything from cellular function to overall metabolic health. Tracing back as far as our hunter-gatherer days, our bodies have evolved to process carbs into energy efficiently.
However, modern society's changing eating habits have distorted our understanding of what suits our bodies, especially with carbs.
Determining the right amount of carbs has become confusing, leading many down a path of metabolic health problems like obesity and diabetes.
Eating too many carbs or the wrong kinds (1) can throw our bodies out of balance, cause energy drops due to the rapid increase and crash in blood sugar levels, leading to an addictive pattern of eating as we constantly need to eat more carbs to maintain energy levels.
This constant reliance on high-carb foods to fuel energy levels may block the body’s ability to burn stored fat for energy.
This could lead to a less efficient metabolism and make it difficult to achieve sustainable weight loss.
People have come to see carbs as the enemy, linking them directly to weight gain, obesity, and associated health issues. This perception drives them to drastically reduce or eliminate such foods from their diet. So, to steer away from the health risks associated with high-carb diets, low-carb and ketogenic diets have become increasingly popular.
However, not every alternative is better. Although low-carb diets might help tap into your fat reserves for energy, unfortunately, they can also downregulate enzyme production and deprive your body of essential nutrients (2), on top of which, they are also hard to sustain.
In an ideal metabolic state, our body should be able to seamlessly transition between burning fats and carbs for energy, adapting to whatever fuel is available.
“Many assume that a healthy lifestyle requires eliminating carbs” shares Lumen nutritionist Abigail Markman. “However, confining ourselves to carb restrictive diets for prolonged periods might inadvertently hamper our metabolic flexibility, and actually prevent us from reaching our health goals.”
“This also might explain people's interest shift in the past years from no-carb diets like Keto to sustainable alternatives, such as Carb Cycling” Abigail adds.
Carb cycling, initially used by athletes to improve performance, has also become a popular nutrition strategy among the wider population, owing to its many metabolic health benefits. This approach involves alternating between high-carb and low-carb days based on your long-term health goals.
Carb cycling plans push the body to resort to fat burn when low on carbs, while high-carb days allow the body to restore energy stores. This can positively influence metabolic health and flexibility.
Metabolic health benefits that stem from a carb cycling plan include:
Everyone's body is unique, and their metabolic health will influence how they best balance and personalize their carbohydrate intake. Assessing your metabolic health will give you a clearer idea and action plan on how to feel your best and live a healthier lifestyle.
Carbs are your body's go-to fuel. When carbohydrates enter our system, they embark on a complex physiological journey. Starting in the digestive tract, these molecules are broken down into simpler sugars like glucose, which then enter the bloodstream.
This rise in blood glucose stimulates the pancreas to release insulin, a hormone critical for both regulating our blood sugar levels and the glucose uptake by cells. As cells absorb glucose, they either utilize it for immediate energy or store it for future use, primarily as glycogen in the liver and muscles. When glycogen stores are full and there is still more glucose going around, our body turns it into fat. The body's adept handling of carbs is a testament to its crucial role in maintaining cellular function, energy balance, and overall metabolic health.
Eating more carbs than your body needs can block fat burn and may lead to a vicious cycle of weight gain, sugar spikes, and insulin resistance.
So for example, when you consume a high-carb meal, your body goes into "carb burn" mode. The carbohydrates in your food are broken down into glucose which enters the bloodstream. Too many carbs on high-carb days may result in weight gain and sugar spikes. This increase in blood sugar levels signals the pancreas to release insulin, a hormone that helps the body's cells absorb glucose for energy or storage (3). However, if this becomes a consistent dietary pattern, the body may struggle to process this increased glucose load efficiently.
This could lead to insulin resistance, a condition where cells become less responsive to insulin, the hormone that enables glucose absorption. Over time, too many carbs on high-carb days may result in insulin resistance, weight gain, and type 2 diabetes, a severe metabolic disorder.
The low-carb and keto diets have been all the rage, but are they really safe? Eating too few carbs can result in metabolic inflexibility, brain fog, keto flu, and other uncomfortable side effects.
On a low-carb or ketogenic diet, your body enters a state of "fat burn." This means your body uses fat as its primary fuel source (4). Over time, this may disrupt your glycolytic pathways, making it difficult for your body to process carbohydrates efficiently when you do consume them.
Additionally, our brains use glucose from carbs as their primary source of energy, and consuming low amounts can result in brain fog or “Keto flu” (5). Too little carbs in low-carb days may also result in uncomfortable side effects, including headaches, dizziness, fatigue, nausea, and constipation.
Not to mention, many very low-carb or Keto diets are challenging to sustain, and dieters will eventually want to be able to include more carbohydrates in their meals which can lead to rapid weight regain.
Whether you fall into a high-carb or keto camp, improperly managing your carbohydrate intake can hold you back from your goals. Very low-carb diets, as well as high-carb diets, can have long-term detrimental effects on our metabolism and metabolic flexibility (8).
Going too low or too high on carbs can mess with your metabolism.
Every person has different carb needs and to adjust to what's good for you to achieve your health goals.
This study (6) published in 2018 found that people who followed diets tailored to their needs and preferences were likelier to adhere to the diet and lose weight.
In a peer-reviewed clinical study published in PubMed (7), Lumen's research team together with Tel Aviv Sourasky Medical Center found that participants who used Lumen’s recommendations for 12 weeks saw improved metabolic parameters. Participants achieved an average weight loss of 6% (13 pounds) and significant reductions in body fat and waist circumference.
According to Lumen Expert, Dr. Dave Asprey, with Lumen you can get a better understanding of what carbs your body needs and when. Watch him explain here:
Contrary to popular belief, carb cycling is not a one-size-fits-all. Why? Because each individual's body responds uniquely to varying carb intakes. For instance, some people might find they thrive and burn energy efficiently with X amount of carbs, while others may feel sluggish or store excess energy as fat with the same amount.
Additionally, even within the same person, metabolic reactions can vary: there might be days when your body burns carbs quickly, and other days when it takes longer. Understanding these fluctuations is crucial.
Hence, a personalized approach is essential. With a dynamic and tailored nutrition plan for the long-run specifying when you should have high-carb and low-carb days, you can optimize your metabolism to align with these individual and day-to-day variations. This Lumen low-carb, carb cycling meal plan pdf can give you some recipe ideas on how to approach
When you take a breath measurement, Lumen guides you through two phases: “fat burn” and “carb boost” days to ensure your body’s metabolism is well trained to burn both carbs and fat.
Carb cycling can have many benefits for our metabolic health. For example, introducing high-quality carbs following several days of fat burn preserves your body’s ability to use carbs for energy and prevents carbs from storing as fat. High-carb days allow your body to replenish glycogen stores in your muscle tissue for improved exercise performance and recovery (9).
Timing high-carb intake days may also be beneficial for weight control (10). Some research studies have found that strategizing high-carb days may improve the function of our appetite-regulating hormones, leptin, and ghrelin.
Alternately, limiting carbs on non-active days may reduce excessive calorie intake from carbs which can assist in weight loss. Low-carb days may also help to improve our body’s sensitivity to insulin, an essential hormone in blood sugar regulation.
Enhanced Metabolic Flexibility
With carb cycling, the body is regularly exposed to varying levels of carbohydrate availability. On low-carb days, the body becomes more adept at utilizing fat for fuel.
On high-carb days, it efficiently uses glucose. Over time, this trains the metabolism to seamlessly shift between these energy sources, which is advantageous for both endurance and high-intensity activities and can also improve overall metabolic health.
Enhanced Fat Burn
On low-carb days, the body will be more inclined to use fat as its primary energy source. When carbs are low, insulin levels are lowered, which can prompt the body to access stored fat for energy.
After a period of low-carb intake, high-carb days can boost metabolism due to an increase in the “thermic effect of feeding” (the increase in metabolic rate due to the energy required for digestion, absorption, and storage of nutrients) and an upregulation of hormones like leptin which increase the feeling of satiety.
Increased Dietary Flexibility and Adherence
Continually sticking to a low-carb or high-carb diet can be challenging and mentally draining. By using a carb cycling meal planner, individuals can enjoy a greater variety of foods. This flexibility can make the diet more sustainable, leading to better long-term adherence and results. For many people, knowing they have high-carb days to look forward to can make the low-carb days more manageable.
Enhanced Hormonal Balance
Prolonged low-carb diets can lead to reductions in key hormones like leptin, PDH, Glycogen synthase, thyroid hormones, and even testosterone. These hormones play a role in metabolism and are important for stable energy balance By incorporating high-carb days, carb cycling can help maintain or boost levels of these hormones, leading to better metabolic function.
Improved Workout Performance and Muscle Health
On high-carb days, the replenishment of muscle glycogen ensures that the muscles have ample fuel for strenuous activities. The increased glycogen storage can improve workout performance and provide a more anabolic (muscle-building) environment. It can also reduce muscle catabolism (breakdown) on low-carb days because the high-carb days ensure muscle glycogen stores remain sufficient over the long term.
Following a meal plan for carb cycling is especially beneficial for those who have performance-focused activities or heavy training sessions planned, as glycogen is a primary energy source during high-intensity exercise.
Reduce Risks of Metabolic Disorders
Being metabolically flexible promotes health and reduces the risk of metabolic disorders by allowing your body to regulate energy use and maintain balanced blood sugar levels effectively. It aids in preventing insulin resistance, a key factor in disorders like diabetes and metabolic syndrome.
We can see in this pilot study of participants with prediabetes, Lumen (a handheld metabolic tracker) usage significantly improved multiple metabolic parameters, demonstrating its potential to deliver better clinical outcomes for patients with T2DM and metabolic syndrome.
While each benefit has its unique impact, their combined effect is a testament to the power of metabolic flexibility. Together, they underline the benefits of a balanced Carb Cycling meal plan. By adopting such a plan, you can unlock improved metabolic health and pave the way for a healthier lifestyle.
While the information on whether you should be eating high-carb or low-carb can be helpful, what does successful carb cycling look like? We’ve got you covered.
Nutrition is personal. Feeding your body with the right type and the amount of carbs that is right for you is how you can get closer to improving your metabolic health and achieving your goals.
One of the most important aspects of achieving success with any nutritional or fitness plan is setting realistic goals. Without attainable objectives, individuals may quickly become discouraged or lose focus.
When you have daily goals and clear milestones, it becomes easier to measure progress and stay motivated. By combining Lumen’s personalized carb cycling planner with well-thought-out goals, you ensure that the regimen is tailored to your needs, increasing the likelihood of long-term adherence and success.
According to this research, setting targets is an important way to develop healthy behaviors that support weight management.
Unlike a generic carb cycling planner, a personalized carb cycling plan is all about optimizing carbohydrate intake in alignment with one's unique body and goals, ensuring efficiency, safety, and success in achieving health objectives
For example, during high carb days (AKA “Boost” days at Lumen), which are only given after three consecutive days of waking up in fat burn, you can train your metabolism to use carbs to fuel workouts and replenish glycogen stores, supporting muscle growth. On low-carb days, you promote fat loss by encouraging the body to burn stored fat for energy.
By aligning your meals with your individual metabolic needs and objectives, a meal plan for carb cycling can help enhance performance, promote weight management, and to achieve various health and fitness goals.
Did you do enough to reach a fat burn? The impact your food choices have on your body can be seen firsthand when you measure your metabolism.
Tracking your performance and understanding your body's reactions to your new dietary change is an essential aspect of achieving your health and fitness goals. By closely monitoring how your body responds to alterations in your diet, you can:
When making big lifestyle changes, it’s important to prepare your environment for success including:
To be successful with a diet plan for carb cycling, it’s essential to understand your body’s specific metabolic needs otherwise, you may not be timing your high-carb and low-carb days properly or eating the right amounts. This can impact your goals and potentially lead to weight gain and low energy levels.
By now, you should be feeling like you have a better understanding about carb cycling and its benefits on your metabolic health and flexibility. Carb cycling meal plans are great for those looking to improve athletic performance, boost post-workout recovery, and might even help with weight loss if done correctly.
Carb cycling correctly takes a clear understanding of what your body needs and can be very difficult and time-consuming to do without proper guidance. That’s why Lumen offers individualized nutrition plans to give you the confidence and results you seek. Having this kind of structured plan personalized just for you can help you form healthy habits to meet and stick with your goals.
If you haven’t already, check out Lumen and start your personalized carb cycling journey today.
The answer varies based on your unique metabolic health, activity levels, and other factors. Lumen can provide personalized daily recommendations based on real-time metabolic data.
Carbs are the body's preferred source of energy. They also provide essential nutrients and support a healthy gut microbiome. While low-carb diets can aid in weight loss, they can also disrupt the body's ability to process carbohydrates efficiently.
High-quality carbs are nutrient-dense and often high in fiber. Examples include whole grains, fruits, vegetables, and legumes. These foods help provide steady energy release, preventing blood sugar spikes and promoting a healthy gut microbiome.
According to research (11), consuming a small amount of carbs can also result in nutrient deficiencies over time, specifically calcium, vitamin D, magnesium, and phosphorus. A deficiency in these essential nutrients can cause problems down the road, especially when it comes to bone health. If you’re following a low-carb diet, plan to enrich it with foods containing soluble vitamins (folate and thiamin), selenium, magnesium, calcium, and iron.
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Marine is a registered dietitian (RD) with extensive experience in clinical nutrition and a deep passion for well-being, health, and metabolism. With her background as a clinical dietitian and private practice owner, Marine has helped patients from diverse backgrounds improve their health through personalized nutrition. Currently, Marine serves as a customer success nutritionist at Lumen, where she provides expert nutrition support to clinics using Lumen’s technology to enhance their clients’ metabolic health. Marine is dedicated to empowering individuals to improve their relationship with food and achieve their health goals.
