For years, diets called for the elimination of fats, urging us to move towards low-fat alternatives. While, like any other nutrient, overdoing fats can lead to weight gain, cutting out dietary fats need not necessarily result in weight loss. Replacing bad fats (trans fats, saturated fats) with good fats (mono and poly-unsaturated fats) comes with benefits that extend beyond weight loss. This article covers everything there is to know about incorporating monounsaturated fats in your diet.
Monounsaturated Fatty Acids
Fats are an important component of any meal as they help in absorbing fat-soluble vitamins and minerals.
They also store energy within the body, protect vital organs, and help in muscle movement.
Fats are chains of carbon and hydrogen, and depending on the length of these chains and the arrangement of these atoms, they are classified into different types of fats.
- Saturated fats
- Polyunsaturated fats
- Monounsaturated fats
- Industrial trans-fats
The “mono” in monounsaturated fats represents the single double bond that is found in its chemical structure.
Owing to this chemical structure, monounsaturated fats are often liquid at room temperature.
History Of Fat Consumption
Anthropologists claim that the diet of early humans was more similar to that of modern chimpanzees. They consumed fruits, vegetables, leaves, flowers, and meat. It is believed that meat was first consumed about 2.6 million years ago.
However, our early ancestors engaged in scavenging food rather than hunting. They consumed the edible portions of flesh that were left behind by the predator. Jesicca Thompson, an anthropologist from Yale University, says that the early humans consumed bone marrow stuck in between the bones of the dead animal rather than the “meat.” The marrows are rich in fat content. Thompson claims that it was around this time that humans started adding fat-rich food to their diet.
Modern-day diet has monounsaturated fats in vegetable and seed oils. A study confirmed that the first use of vegetable oil, particularly olive oil, was seen around 8000 years ago in the Middle East. But it was in the 1600s when people started making oil from vegetables.
The 1800s saw the widespread use of vegetable oil as the commonly used whale oil became expensive. In the process of making affordable soaps using cottonseed oil, two industrialists in Cincinnati took the opportunity to introduce it in the food industry. In a few years, animal fats were replaced by vegetable cooking oils, and we can still find them in our kitchens today.
Studies observed that people from the Middle East or the Mediterranean countries had a lower risk of heart diseases, despite consuming a fat-rich diet. Further investigation showed that their diet included olive oil and other seed oils as their main source of fat and not animal fat. This could mean that the health benefits come from unsaturated fats rather than saturated fats from animals.
Importance of Monounsaturated Fatty Acids
A study consisting of around 840,000 adults aged 4-30 years found that the consumption of monounsaturated fats reduced the risk of heart disease by 12%, compared to the control group (little to no monounsaturated fats consumption)
Monounsaturated fats improve overall health by:
- Reducing the risk of cancer
- Reducing the risk of diabetes
- Improving blood cholesterol levels
- Helping in maintenance and development of cells
- Improving insulin sensitivity
- Reducing inflammation
Sources of monounsaturated fats are olive oil, peanut oil, avocados, nuts, safflower, and sunflower oils.
Is There A Relationship Between Monounsaturated Fats And Weight Gain?
Weight gain is caused when the calories consumed are greater than the calories burnt.
All fats provide the same amount of energy, which is about nine calories per gram.
Based on your lifestyle and your basal metabolic rate, including the right amount of fat in your diet, can help with weight management.
Even though weight gain/loss is a simple equation of calories in and out, the quality of the food you eat as part of your diet is very important.Some studies have shown that if calorie intake remains the same, diets high in MUFAs lead to weight loss and could even be more effective than a high-carb diet.
What Is The Recommended Amount Of Monounsaturated Fat Intake?
It is recommended to use monounsaturated fats as a replacement to saturated or trans-fats as much as possible.
The 2015 Dietary Guidelines for Americans suggest that fats should be limited to 25 to 30% of the total daily calories; this includes all types of fats.
How Do Genes Affect The Relationship Between Monounsaturated Fats And Weight?
ADIPOQ
This gene is involved in the control of fat metabolism (break down) and insulin sensitivity (how well your body responds to insulin) in the body.
Changes in this gene directly affect anti-diabetic, anti-atherogenic (preventing fatty deposit formation), and anti-inflammatory activities.
The gene codes for a protein called the adiponectin, that is involved in aids fatty acid breakdown. Higher the adiponectin levels, more efficient the fatty acid breakdown.
Decreased adiponectin levels are thought to play a central role in obesity and type 2 diabetes.
Changes in lifestyle, such as incorporating exercise and a following balanced diet, that result in weight loss, can lead to an increase in adiponectin concentration and increase insulin sensitivity.
rs17300539
A study found that a variation rs17300539 in the ADIPOQ gene can lead to a difference in blood adiponectin levels.
Individuals with a G allele have lower blood adiponectin levels when compared to those with an A allele. Carriers of the A allele (AA/AG), therefore, had lower weight, BMI, waist, and hip circumferences.
While considering the monounsaturated fats intake of greater than 13% of the total energy intake, the A allele carriers had a considerably lower BMI compared to GG carriers.
This shows a relationship between the effect of a gene on monounsaturated fats intake and weight.
NR1D1
NR1D1, also known as Rev-ErbA alpha, is present in the liver, skeletal muscles, adipose (fat) tissues, and the brain in mammals.
Adipogenesis is the process by which adipocytes, or fat cells are formed.
Rev-ErbA alpha includes adipogenesis and could be a potential target for novel anti-obesity treatments.
rs2314339
A study analyzed the association between NR1D1, monounsaturated fats intake, and weight in North American and Mediterranean populations.
People with the AA and AG types had a lower waist circumference and a decreased risk for obesity than people with the GG type.
The A allele occurrence was also significantly low in the ‘abdominally obese’ group.
There was also a significant interaction for obesity with NR1D1 and monounsaturated fats intake in the Mediterranean population.
Individuals with the A allele had higher protection against obesity with diets rich in monounsaturated fats. (>55% of total fat).
PPARG
PPARG is a gene predominantly present in adipose tissue. It plays a role in adipocyte differentiation (converting one type of cell to another), regulating glucose levels, and insulin signal transduction (communication between two cells).
A change in this gene has been studied to play a role in increased sensitivity to insulin and a more favorable lipid profile.
rs1801282
A study recruited overweight subjects between the ages of 20-65 years in southeastern Spain.
They analyzed the subjects as they underwent a treatment program for obesity.
This included analyzing the diets and the number of calories expended during exercise.
They found a gene-diet interaction between PPARG and monounsaturated fats intake.
People who had the G allele (CG/GG) were significantly less obese than those with the C allele (CC) - when monounsaturated fats intake was high (>56% of total fat).
This difference disappeared in low monounsaturated fats diets.
Overall, in each case, diets with high monounsaturated fats intake (>55% of total fat) resulted in a greater weight loss in individuals.
Food Sources Of MUFA
Most foods have a combination of all types of fats. Foods and oils that have a higher percentage of MUFA are:
- Nuts: Almonds, peanuts, pistachios, and cashews
- Avocado
- Olives and olive oil
- Pumpkin and sunflower seeds
- Eggs
- Peanut butter and peanut oil
- Sesame, safflower, and canola oil
Summary
Fats are a necessary component in a balanced diet. However, not all types of fats are healthy. While saturated fats are the ‘bad fats,’ the unsaturated fats are ‘good fats.’ Monounsaturated fats or MUFAs are fats joined by a single bond. They help reduce the risk of health conditions like diabetes and cancer. They also enhance insulin sensitivity and, therefore, play a role in weight management. Several genes ADIPOQ, NR1D1, and PPARG, mediate how your body responded to MUFAs in terms of weight gain. People with certain types of these genes tend to benefit more from MUFA consumption in terms of weight loss and can include more MUFA-rich foods in their diets. Some food sources of MUFAs include avocados, olive oil, peanuts, and eggs. Even though MUFAs are present in certain animal sources like red meat, their benefits are negated by the saturated fats in them.
Reference
- https://www.nature.com/scitable/knowledge/library/evidence-for-meat-eating-by-early-humans-103874273/
- https://insidescience.org/news/importance-fat-early-human-evolution
- https://www.academia.edu/9517113/Olive_oil_storage_during_the_fifth_and_sixth_millennia_BC_at_Ein_Zippori_Northern_Israel
- https://www.health.harvard.edu/staying-healthy/the-truth-about-fats-bad-and-good/
- https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4198773/
- https://www.healthline.com/health/what-is-basal-metabolic-rate
- https://www.medicalnewstoday.com/articles/323027
- https://www.medicinenet.com/script/main/art.asp?articlekey=17982
- https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5486142/
- https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2753535/
- https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4059404/
- https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3951915/