The 4 pillars of health include diet, sleep, stress reduction/mindset and exercise. Addressing these 4 key areas, for most people, would lead to a significant improvement in their health, from how they feel to how they look.
When looking at diet specifically, if people simply ate more nutrient dense, unprocessed/whole-foods foods and less processed foods, regardless of how much protein, fats or carbs they ate, they would see huge differences in their health. However, for some people, adjusting macronutrient ratios (e.g. low carb or high carb) can help achieve a specific therapeutic effect and may be helpful in some situations.
Carbohydrates are a macronutrient that is commonly adjusted in people’s diets to help achieve certain therapeutic effects. The most common is for weight loss purposes.
In this post I want to outline a few situations where adjusting carbohydrates in a persons diet may be of benefit.
1) When could a very low carb approach be useful?
A very low carb diet usually means carbs are eaten at amounts of less than 50g per day. This would usually mean that a person would get most of their carbs from fruits and vegetables. More higher carb foods like grains and starchy vegetables (e.g. sweet potato) would have to be very limited and in very small amounts.
Glucose from carbohydrates is the main fuel source for the brain and nervous system. Fat cannot be used for energy production in the brain, therefore, when there is a lack of carbohydrates in the diet to support the needs of the brain and nervous system, the body has a backup plan where it converts fat stores or fat ingested into ketones.
Ketones can be burnt for energy in the brain and nervous system. The body will also break down muscle protein, which can be converted into glucose and ketones. This is why on a low carb diet it is important to eat adequate amounts of protein in order to retain muscle mass.
One can know if they are in ketosis by checking their urine using keto sticks and a person’s breathe usually smells of acetone during ketosis, as ketones are acidic.
A very low carb approach and ketosis has been shown to be helpful in people who have neurological issues like dementia, Alzheimer’s, epilepsy, ADHD, autism, and Parkinson’s. When the brain burns ketones for energy production it has a neuro-protective effect on brain cells. The brain seems to metabolize ketones better in these conditions.
2) When could a low carb approach be useful?
A low carb diet can be used to help control blood sugar levels and improve insulin sensitivity in those who have full-fledged type 2 diabetes or are pre diabetic (metabolic syndrome). This is because carbs (glucose) require insulin to help glucose get into cells. Therefore, reducing the need for insulin can help to improve insulin sensitivity.
It can also be used for people who want to try and lose weight. Reducing carbs, by default, leads to a decreased intake of calorie dense, processed foods, and leads to a net increase in protein intake, which is our most satiating nutrient. Therefore allowing people to feel fuller for longer, decreasing the chances of over eating. It also, prevents muscle loss, which can occur during weight loss.
Despite this, in order to lose weight, one must be in a caloric deficit. Whether a person decides to go low car or low fat, over the long term, it actually does not matter for weight loss. As long as the person is in a caloric deficit, they stick to the diet and they eat adequate amounts of protein. Reducing carbohydrates in a caloric deficit, simply allows the body to burn body fat as a fuel source.
Lastly, a low carb approach could be used for women suffering from polycystic ovarian syndrome (PCOS). This is because a low carb diet helps to improve insulin sensitivity and insulin resistance, which is one of the core features in PCOS. Insulin resistance in women up-regulates enzymes that convert estrogen to testosterone excessively and high testosterone levels in women lead to the symptoms of PCOS such a amenorrhea/oligo-menorrhea, acne, abnormal body hair growth, hair loss and infertility.
Eating on a low carb protocol would be around 150g of carbs per day. This is the most common form of low carb eating and it is enough to fill the liver with glycogen.
For a person on a low carb diet, it is important that they make sure they are eating enough fruit and vegetables. This is because fruit and vegetables contain soluble fiber, which is food for our good bacteria in our gut. I mention this because sometimes people go on low carb diets where they end up restricting a lot of fruits and vegetables, which in turn compromises the health of their gut and the composition of our gut flora is essential to health.
It must be noted that some people feel really good on a low carb diet and others feel really average. This may be due to differences in genetics, as well as changes in the gut micro-biome. Decreasing carbs can lead to a decrease in gut bacteria that produce serotonin for the brain. Low serotonin levels in the brain can lead to arb cravings as carbohydrates increases serotonin.
3) When can a moderate carb approach be useful?
A moderate carb diet is usually considered to be 250g of carbs per day. For a reference, average Australians eat over 300g. This approach doesn’t impair muscle performance and it confers the metabolic benefits of a lower carb intake in people who are diabetic and/or overweight/obese.
A moderate carb diet should be followed for individuals who are generally healthy, they exercise moderately or don’t exercise at all and want to maintain their weight.
Furthermore, a moderate carb approach should occur when a low carb or very low carb approach could be harmful or detrimental. There are a few instances where a low carb intake could be problematic. These include:
1) People who are chronically stressed. Chronic stress raises cortisol levels and reducing carbohydrates can also lead to increased cortisol levels. This is because cortisol is released to break down muscle in order to use the protein to convert to glucose. When a person is chronically stressed it would not be ideal to raise cortisol levels any further. If this does occur, it is vital that extra protein is incorporated into the diet in order to prevent muscle loss. Stressed people also have fluctuating blood glucose levels.
2) People who have hypothyroidism. This is where a person’s thyroid gland is functioning at a less than optimum level, causing a reduction in metabolic rate, as the thyroid gland regulates our metabolism.
Insulin is important for the conversion of inactive thyroid hormones (T4) to the active form of thyroid hormone (T3). Insulin is raised when we eat carbs because insulin is needed to help shuttle glucose into cells. Therefore eating carbs is essential to healthy thyroid function and long-term low carb diets can lead to hypothyroidism.
This is why on a low carb diet it is important to do a carb reefed every so often. Hypothyroid symptoms from a low carb diet can usually result in symptoms like weight gain, cold intolerances, hormonal issues, reproductive issues, cognitive issues, fatigue, hair loss and sleep issues.
3) Over exercising and not eating enough carbs to sustain workout loads can increase stress and cortisol levels in the body. Chronically high cortisol levels have a whole host of detrimental health effects.
4) When can a high carb approach be useful?
A high carbohydrate diet is often necessary for athletes and very active people. Carbohydrates are the most efficient fuel source for our bodies during high intensity exercise.
If your activity levels, sport or training regimes include long bouts of high intensity cardio, strength work or both, then carbs are essential. The only time where a high carb diet may not be ideal for athletes is those who are involved in power sports like power lifting, which requires maximal strength for very short periods of time. For these individuals, a high carb diet may lead to weight gain as their energy needs are less.
Fat is an inefficient fuel source to be burnt for people working at a high intensity. It requires more oxygen than carbs to produce energy for the body. Therefore if you are an athlete that performs at a moderate to high intensity for extended periods of time, then not eating enough carbs can decrease performance. It can also lead to negative health effects as this is seen as a major stressor to the body. Symptoms can include weight gain, fatigue, decreased recovery time, muscle loss and hormonal issues that effect sexual and reproductive wellbeing.
A high intake of carbohydrates is important for putting on muscle, as insulin is an anabolic hormone, which is increased by eating carbs.
Lastly, if you are pregnant or breastfeeding then a high carb diet may also be necessary as glucose is an important fuel for the fetus’s growth. Also, pregnancy and breastfeeding is a time where energy needs increase, therefore they need to be supported. You may want to caution against a high carb diet if you have gestational diabetes or were diabetic before pregnancy.
5) Eating carbs only at certain times or days (aka targeted or cyclical ketogenic dieting)
Everyone has actually tried a low-carb diet before. That’s because everyone’s low-carb between meals.
Most people are only low-carb for around ten hours, eight hours of sleep plus a couple more hours. Others are low-carb for many years. But there’s actually a standardised low-carb diet that falls between those extremes.
Its called the cyclical ketogenic diet (CKD), which basically involves low-carb weekdays and carb refeeds on the weekend. This diet is especially beneficial for athletes or those interested in fine tuning body composition, since you can drastically lower calories for most of the week then fuel exercise with carbs for a day or two. CKD is just one form of intermittent carbohydrate restriction, which has shown benefits in a few trials.
There’s one other way you can restrict carbs, by only eating carbs around workout time (TKD, or targeted ketogenic diet). All of these diets are ways to play around with energy restriction based on timing, with the most popular form being intermittent fasting.
You can also modify carb intake in creative ways other than just eating less every day. For example, eating less on certain days, not eating much carb when you’re not working out much, or just fasting for a large portion of the day.
As you can see, manipulating carbohydrate intake can be useful in certain situations to achieve certain therapeutic effects. But as I’ve said many times on my blog, when it comes to nutrition, there is no one size fits all approach. When changing your diet you should stay flexible. Keep an eye on how you feel and react to the changes and adjust accordingly. Keeping some kind of food diary can help.
Also, if you are manipulating carb intake to treat a certain condition, monitor if your symptoms improve. It is important that the carbs you are consuming are of good quality from whole, minimally processed foods such as whole grains, beans, legumes, potato, sweet potato, pumpkin and fruits. These foods provide many beneficial nutrients beyond their calories.
Lastly, it is also important that even though you are changing your carb intake, the rest of your diet needs to be balanced.