Do Carbohydrates Make You Gain Weight?

Types Of Carbohydrates

Carbohydrates are one of the primary macronutrients found in food, and they come in various forms.

The main types of carbohydrates include sugars, starches, and fibers:

1. Sugars: These are the simplest form of carbohydrates and include glucose, fructose, and sucrose. Sugars are found naturally in foods like fruits, vegetables, and milk or added to processed foods.
2. Starches: Starches are complex carbohydrates composed of many sugar units linked together. Foods like grains, potatoes, and legumes are high in starches.
3. Fibers: Unlike other carbohydrates, fibers are not digested in the human body. Instead, they pass through the digestive system, contributing to satiety and gut health. Dietary fiber is abundant in fruits, vegetables, whole grains, and legumes.

Carbohydrates: Some Facts

Carbohydrates are a primary energy source for the human body.

Once consumed, they are broken down into glucose, which provides fuel for bodily functions.

However, the impact of carbohydrate consumption on the body can vary significantly depending on the type of carbohydrate.

Simple sugars are rapidly absorbed into the bloodstream, leading to a quick surge of energy and potential blood sugar spikes.

Complex carbohydrates and fibers are digested more slowly, providing sustained energy and contributing to satiety.

The latter is beneficial for weight management, as it can help reduce overall calorie intake.

Do Carbohydrates Make You Gain Weight?

The role of genetics in weight gain and carbohydrate metabolism is a complex and rapidly evolving field.

Several genes have been identified that may interact with carbohydrate intake to influence body weight.

FTO (Fat mass and obesity-associated protein) Gene

The FTO gene is one of the most well-studied genes in relation to obesity risk.

Variants of this gene, such as the SNP rs9939609, have been associated with a higher risk of obesity and seem to interact with dietary carbohydrates.

Individuals with certain FTO variants may show greater weight loss on a low-carbohydrate diet compared to other dietary interventions.

A study published in “The BMJ” in 2012 analyzed the interaction between FTO genotype and carbohydrate intake in relation to body fat mass.

They found that among individuals with the FTO risk allele, higher carbohydrate intake was associated with higher fat mass.

However, the effect of these variants may be modifiable through dietary changes, suggesting that individuals with FTO risk variants might benefit from lower carbohydrate intake.

Check your AncestryDNA, 23andMe raw data for the FTO gene variants

AMY1 (Amylase, alpha 1A) Gene

Another gene that might impact weight gain related to carbohydrate intake is the AMY1 gene.

This gene codes for salivary amylase, an enzyme that begins the breakdown of dietary starch in the mouth.

The copy number variation (the number of copies of a particular gene in the genome) of AMY1 has been shown to influence obesity risk.

A study published in “Nature Genetics” in 2014 found that individuals with a lower copy number of AMY1, resulting in less salivary amylase production, had a higher risk of obesity.

This could be because lower salivary amylase production might affect the digestion and absorption of starch, potentially leading to weight gain.

Check your AncestryDNA, 23andMe raw data for the AMY1 gene variants

MC4R (Melanocortin 4 receptor) Gene

The MC4R gene, which plays a role in regulating appetite and energy expenditure, may also interact with carbohydrate intake to influence weight.

Variants of MC4R have been linked to increased obesity risk, but the relationship between MC4R, carbohydrate intake, and weight is still not fully understood and needs further exploration.

Check your AncestryDNA, 23andMe raw data for the MC4R gene variants

Personalized Nutrition

The study of genetics and weight gain related to carbohydrate intake is part of the broader field of nutrigenomics, which examines how genes interact with dietary factors to impact health outcomes.

This research could pave the way for more personalized nutrition recommendations based on an individual’s genetic profile.

However, it’s important to note that genetics is just one piece of the puzzle.

Lifestyle factors, including overall diet quality, physical activity levels, sleep, and stress management, also play significant roles in weight management and health.

Do All Carbohydrates Cause Weight Gain?

Not all carbohydrates are created equal when it comes to weight gain.

Simple carbohydrates, particularly those in processed foods, can contribute to weight gain because they are easily overconsumed and rapidly absorbed.

This leads to blood sugar spikes and subsequent crashes that can stimulate overeating.

On the other hand, complex carbohydrates, especially those high in fiber, have been associated with weight loss.

They provide sustained energy, promote satiety, and are typically found in nutrient-dense foods, making them a healthier choice.

Should You Avoid Carbohydrates Completely?

Given the widespread belief that carbohydrates can cause weight gain, you might wonder if you should avoid them altogether.

However, this is neither necessary nor beneficial for most people.

Carbohydrates are a crucial source of energy and are found in a wide variety of nutritious foods.

Instead, the focus should be on choosing high-quality, nutrient-dense carbohydrate sources, such as whole grains, fruits, and vegetables. Limit the intake of processed foods high in added sugars and refined grains.

Food Sources That Have Low Carb Content

If you are looking to reduce your carbohydrate intake, many nutritious foods are low in carbohydrates:

• Protein sources: Foods like lean meats, fish, eggs, and tofu are high in protein and low in carbohydrates.
• Non-starchy vegetables: Most vegetables are low in carbohydrates. This includes leafy greens, broccoli, bell peppers, zucchini, and cucumbers.
• Healthy fats: Avocados, olives, and nuts are low in carbohydrates but high in heart-healthy fats.
• Berries: While fruits generally contain carbohydrates, berries are relatively low in carbs and high in fiber.

Takeaway

Carbohydrates play an essential role in human nutrition. Their impact on weight can vary significantly depending on the type of carbohydrate and individual genetic factors.

While certain carbohydrates may contribute to weight gain, others can support weight management and overall health.

Therefore, the quality and source of carbohydrates matter more than the quantity alone.

Rather than avoiding carbohydrates completely, it’s better to choose high-quality, nutrient-dense carbohydrate sources and limit your intake of processed foods.

References:

1. Ludwig, D.S., et al., (2018). Dietary carbohydrates: role of quality and quantity in chronic disease. BMJ, 361: k2340.
2. Locke, A.E., et al., (2015). Genetic studies of body mass index yield new insights for obesity biology. Nature, 518(7538): 197–206.
3. Atkinson, F.S., et al., (2008). International Tables of Glycemic Index and Glycemic Load Values: 2008. Diabetes Care, 31(12): 2281-2283.
4. Falchi, M., et al., (2014). Low copy number of the salivary amylase gene predisposes to obesity. Nature Genetics, 46, 492–497.
5. Qi, Q., et al. (2012). FTO Genetic Variants, Dietary Intake and Body Mass Index: Insights from 177,330 Individuals. Human Molecular Genetics, 23(25): 6961–6972.
6. Falchi, M., et al. (2014). Low Copy Number of the Salivary Amylase Gene Predisposes to Obesity. Nature Genetics, 46, 492–497.
7. Loos, R. J. F., & Janssens, A. (2017). Predicting Polygenic Obesity Using Genetic Information. Cell Metabolism, 25(3), 535-543.