What is Carb Cycling & Keto Cycling
The ketogenic diet is well known for its ability to promote fat loss. And if you’ve been reading my articles over the last few months, you also know about its numerous benefits for Alzheimer’s, PCOS, cancer, acne, traumatic brain injury, and more.
You probably also know that the keto diet is one that is very low in carbohydrates. Carbs are often considered “the enemy” when it comes to maintaining a state of nutritional ketosis.
But (as usual) the truth lies somewhere in the middle…
In fact, some research indicates that adding carbs to your diet – strategically – can actually help break through weight loss plateaus, balance hormones and make the keto diet work even better!
In this article, you’ll discover:
- The potential pitfalls of a long-term, low-carb diet
- The unique cases that indicate more carbohydrates could be beneficial
- The concepts of “keto cycling” and “carb cycling” and how they differ
- The benefits of utilizing carb strategies, plus how and when to use them
- Examples of keto and carb cycling, plus delicious meal ideas to get you started!
Potential Drawbacks to the Keto Diet
For many people, the first few weeks on keto can be a rough adjustment. This is especially true for those coming from a high-carb diet. The “keto flu”, as it is called, can bring an onslaught of unpleasant symptoms, including irritability, insomnia, brain fog, headaches, muscle soreness and more.
The good news is that these symptoms typically resolve in a couple weeks, as your body makes the switch from using carbohydrates to primarily using fat to produce energy.
However, for some people, restricting carbs too much – or for too long a period of time – can lead to other long-term issues. Let’s take a look at the potential hormonal drawbacks to long-term carbohydrate restriction.
Hormone Imbalances: T3, Cortisol and Leptin
Many hormones – including thyroid hormones, leptin and cortisol – are impacted by carbohydrates in the diet. And for some people, carbohydrate restriction can cause hormonal disruptions.
For example, women who adopt a very low-carb or ketogenic diet that contains too few calories – especially when these women lose too much weight and/or exercise excessively – may stop menstruating. This is known as hypothalamic amenorrhea and can indicate a need for more carbohydrates in the diet (or less exercise and more calories).
Let’s look at the biochemistry behind carb restriction and how it can influence these important hormones…
In a previous article, I discussed the many benefits of a low carb or keto diet for thyroid issues, including autoimmune thyroid disease (Hashimoto’s).
The basis for this is pretty straightforward: Blood sugar dysfunction negatively impacts thyroid hormones and blood sugar balance is vital for healthy thyroid function.
However, long-term carb restriction can cause T3 thyroid hormone to drop. And while this could be interpreted as worsening thyroid function, some experts believe it is an indication the body is becoming more sensitive to thyroid hormones. As less T3 is required to achieve the desired effect, the body decreases production.
Because we are all unique, the impact of long-term carb restriction on thyroid function will differ among individuals.
Are your thyroid antibodies going down on a low carb or keto diet? Do you have more energy and less brain fog? Is your weight stabilizing and your mood improving?
If so, these are good signs that your diet is working to optimize your health. On the other hand, if you feel lethargic and moody and see no improvements in thyroid antibodies, this may indicate you need more carbohydrates to optimize thyroid function.
Cortisol: The Stress Hormone
The hypothalamic-pituitary-adrenal (HPA) axis a major control center that dictates how the body uses calories. And one of the key players is the corticosteroid hormone, cortisol.
Some research shows that fasting and a ketogenic diet can increase cortisol levels. But as we just discussed with thyroid hormones, this isn’t necessarily a bad thing.
In fact, while it is known as a “stress hormone”, cortisol has a number of benefits, including reducing inflammation and promoting fat loss. However, too much cortisol can actually have the opposite effects – boosting fat storage and reducing estrogen. This is because the corticosteroids both synergize and antagonize the effects of insulin.
Just like the thyroid hormones, the connection between keto and cortisol is complex and varied. Biochemical pathways are constantly in flux. For example, cortisol levels are affected by production. However, they are also impacted by clearance and regeneration (the process of converting inactive cortisone to active cortisol).
And because cortisol tests measure these elements differently and are simply a snapshot from a given moment in time, it can be difficult (and expensive!) to get a clear picture of the overall cortisol pattern.
What we do know is that metabolic syndrome is tightly linked with unhealthy cortisol patterns… and the keto diet is highly effective nutritional therapy for metabolic syndrome. In fact, the keto diet has been shown to beneficially affect the cortisol pathways in people who are overweight with deep belly fat and markers for heart disease. As Amber O’Hearn of Ketotic.org states:
“If the cortisol pattern that develops in response to a ketogenic diet were the kind associated with metabolic syndrome, we would expect people on ketogenic diets to show signs of abdominal fat gain, rising blood sugar, and worsening cholesterol profile. But we see the opposite. This makes it highly unlikely that ketogenic diets raise cortisol in a harmful way.”
While the keto diet may beneficially affect those individuals struggling with metabolic syndrome and related issues, the case may be different for leaner people without these metabolic issues, and for women in different phases of their reproductive life.
If you’ve been on a carb-restricted diet for some time and are struggling with insomnia, symptoms of adrenal fatigue (HPA axis dysfunction), or poor recovery from exercise, strategically adding carbohydrates may improve your cortisol response and long-term health.
Leptin: The Satiety Hormone
Leptin is a hormone produced by your body’s fat cells. Often called the “satiety hormone” or the “starvation hormone”, leptin assesses your energy availability. If you have enough body fat, leptin tells your body it can burn calories normally.
Leptin is also involved in reproductive function as females have leptin receptors in the ovaries. This makes sense because healthy reproduction is dependent upon energy availability. “Starvation mode” is a clear signal that a woman’s body cannot support a healthy pregnancy.
As a woman, if you aren’t consuming enough calories or overly restricting carbohydrates, you could alter leptin’s ability to regulate your reproductive hormones. And because insulin stimulates leptin synthesis, this can further reduce leptin levels.
If you’re experiencing cycle-related issues on a very low carb or keto diet, this may indicate a need to add in a few more carbs.
The Case for Carbs: Personalizing Your Carbohydrate Intake
The full keto diet or a long-term very low-carb diet can be highly beneficial for most people. But it isn’t right for everyone at every stage of life. As you just learned, you may need to personalize your diet, depending on your unique biochemistry, activity level, and hormonal responses.
Here are some quick tips to guide your carb consumption.
You may need MORE carbohydrates if:
- You are pregnant or breastfeeding
- You lose your period or have irregular cycles (perimenopause)
- You are highly active (especially with high-intensity workouts / heavy lifting)
- You begin having trouble recovering from workouts
- You have thyroid issues that seem to worsen on a carb-restricted diet
- You have adrenal fatigue
- You struggle with insomnia
- Your body fat is very low
You may need LESS carbohydrate if:
- You have brain-related disease like Alzheimer’s, Parkinson’s or traumatic brain injury (TBI)
- You have PCOS, fibroids or endometriosis
- You have yeast overgrowth, SIBO or other digestive issues, related to carbohydrate intake
- You are diabetic or insulin resistant
- You have cancer
Now you’ve learned about the primary hormonal imbalances that can occur in some people on long-term carb-restricted diets. You’ve also discovered the symptoms and conditions that may indicate a need for more carbs.
Let’s delve into the options for adding carbohydrates back into your diet strategically… how to plan your carb or keto cycling… plus some delicious, nutrient-dense sample meals to get you started.
Keto Cycling & The Carb Refeed
Keto cycling is just what it sounds like: You eat in a way that allows your body to cycle in and out of ketosis. And while this can be tweaked to your unique needs, most people choose to eat less than 50 grams of net carbs for six days of the week. Then, increase carbs to around 150 grams on the seventh day. This is known as a “carb refeed” day.
One primary reason why people choose to cycle in and out of ketosis strategically is to improve body composition. That’s right… consuming carbs might actually improve your physique!
When you eat the same way consistently, your body adapts to your eating pattern over time. This is why many people reach a weight loss plateau on a low-carb or keto diet.
By adding a carb refeed day, your leptin levels also get a boost. Not only does this benefit your perception of hunger, it also helps to prevent your metabolism from going into “conservation mode” where it tends to hold on to fat for survival.
With a strategic carb refeed, many people report higher energy levels, greater weight loss and fewer cravings.
It is an important distinction that a carb refeed is not a “cheat day”. This isn’t a day to go hog wild on bread, pasta and pizza. It’s about replenishing your glycogen stores with the Paleo-friendly whole food carbohydrates we note below.
Now let’s look at how a keto cycling differs from carb cycling…
Carb Cycling: Adjusting Carb Intake to Your Activity Levels
The key difference is that a carb cycling diet tends to be a diet high in protein, moderate in fat, and without a focus on maintaining ketosis. In fact, carb cycling often depends on adjusting carb consumption based on activity levels.
While there are many ways to carb-cycle, most people choose to switch between low carb, moderate carb and high carb throughout the week. The low-carb days help sensitize your cells to insulin and assist your body to use carbohydrates more efficiently. Those low-carb days also help your body tap into fat stores to peel away that layer of unwanted fat.
The higher-carb days help to build muscle. If your calories or carbohydrate levels are too low, you may inhibit muscle growth, as the muscles utilize glycogen from carbohydrates in order to grow.
Of course, greater more muscle mass means you’ll burn more calories through the day – even at rest. So, your metabolism gets a boost too!
Now, this is not to say that you cannot build muscle while consuming a keto or low-carb diet. In fact, a study of 25 college-aged men compared a traditional Western diet against the ketogenic diet for muscle gain, strength, and performance. They found that both diets were equally effective.
Interestingly, the keto diet group enjoyed a carb refeed at week 10 which correlated with an increase in lean body mass during that same period.
Another study showed that a very low-carb keto diet in elite gymnasts for 30 days decreased body weight and body fat, without negatively impacting strength.
Similarly, a study in in overweight women found that the combination of resistance exercise with a ketogenic diet reduced body fat without significantly changing lean body mass… while resistance exercise on a regular diet increased lean body mass without significantly affecting fat mass.
The key seems to lie in the strategic addition of carbohydrates (especially if you have been very low carb or keto for some time), and taking your own body composition goals into account.
How Do You Know When to Add More Carbs?
In general, your carbohydrate intake should be dictated by your activity level.
On days when you do harder workouts – such as HIIT, sprints or weight lifting – your body will be more sensitive to insulin. It can tolerate more carbohydrates and utilize those carbs for muscle growth.
On days when you do lighter activity – such as walking, gardening or yoga – your insulin sensitivity will be lower, and consuming fewer carbs would be wise, as they will more likely be stored as fat.
Your macronutrient ratios on carb cycling will look different based on your goals. If you aim to increase muscle mass, your carb intake on the higher-carb days will be more than if your goal is weight loss.
Carbohydrate Foods to Choose for Keto & Carb Cycle
When adding carbohydrates back to your diet, choose those foods that are closest to what our ancestors enjoyed, while taking into consideration your own sensitivities*. Here’s a quick list of Paleo-friendly carbs to choose:
- Sweet potatoes
- Purple sweet potatoes
- Butternut squash
- White rice*
- Potato starch*
Carb Cycling Sample Meal Plans
Now that you’ve learned about the potential benefits of carb cycling and carb refeeding, you might wonder what this way of eating looks like.
If you search the internet, you’ll find carb cycling plans with up to 250 grams of carbs per day. However, unless you are a very large person, with a high metabolism and excellent insulin sensitivity, who does a lot of heavy exercise, this is an excessive amount of carbs. Case in point – 250 g of carbohydrate is equivalent to a whopping 11 bananas or 7 baked potatoes!
A more reasonable upper limit on carbs during a “refeed” is around 100 grams. And as with most things in the world of nutrition, adjust to your own personal needs.
Here are a few sample meal plans, illustrating how to pair activity with carb cycling.
High-Carb Day Sample Meal Plan
Activity Indicator: Intense activity – HIIT, sprints, heavy lower body weight training
Carb target: Up to 100 grams, ideally root veggies at each meal
Include carbs: At each meal
- Breakfast: Pastured Egg Omelet with Tomatoes, Mushrooms & Onions + Organic Home Fries
- Lunch: Wild Salmon Burger + Caramelized Onions + Roasted Sweet Potato
- Dinner: Roasted Free-Range Chicken Breast + Purple Potato Puree + Arugula Salad with Lemon Vinaigrette
Moderate-Carb Day Sample Meal Plan
Activity Indicator: Moderate activity – hiking, jogging
Carb target: Up to 50 grams
Include carbs: At breakfast
- Breakfast: Scrambled Eggs + Sweet Potato Pancakes with Grass-Fed Butter
- Lunch: Wild Salmon Burger + Organic Green Salad
- Dinner: Grass-Fed Flank Steak + Pepper, Mushroom & Onion Stir-Fry
Very-Low Carb Day Sample Meal Plan
Activity Indicator: Light activity – walking, gentle yoga
Carb target: 20- 30 grams
Include carbs: Minimally, from above-ground vegetables
- Breakfast: Meat-Lover’s Omelet with Pastured Pork Sausage & Grass-Fed Cheddar Cheese
- Lunch: Wild Shrimp Cocktail with Easy Mayo Remoulade + Organic Green Salad
- Dinner: Grass-Fed Beef Burgers in Lettuce Wraps with Pickles, Mayo & Avocado
You are Unique & Your Diet Should be Too!
Your ideal carbohydrate intake will depend on your own genetics, life phase and activity level.
If you choose to increase your carbohydrates strategically, track your progress to see how your body responds. A journal is a wonderful tool for this, and many apps are also available to help make keto cycling or carb cycling accessible.
Also, remember that a tape measure is a far better indication of improved body composition than the scale, as muscle is denser than fat.
Have you experimented with carb cycling or keto cycling? If so, what were your results?