Saturated Fats Overview
Saturated fats are dietary fats that contain carbon, oxygen, and hydrogen molecules. These types of fats have saturated hydrogen molecules and just one bond between the carbon molecules. As a result, saturated fats remain in a liquid state when the temperature is high and solidify when the temperature drops.
Saturated fats are a common source of fat in the American diet.
Why Are Saturated Fats Considered Unhealthy?
Several studies have proved that excess saturated fat intake increases the risk of the below conditions.
Cardiovascular diseases
Hyperlipidemia (excess lipids in the blood)
Type II diabetes
Obesity and weight gain
Weight gain is a common problem with increased saturated fats intake. Saturated fats add extra calories to your meals and increase your LDL cholesterol levels. These steadily cause an increase in body weight.
Saturated Fats At The Molecular Level - Getting Technical
The digestion of saturated fats starts from the minute you consume fatty food. Saliva contains enzymes that break down fats into smaller molecules. The act of chewing food also helps in breaking down the particles. From here, fat molecules reach the stomach. The bile and stomach enzymes work on saturated fats and break them down into even smaller components. The very small fat molecules reach the bloodstream directly. Bigger ones get passed on to the intestine. In the intestine, fats get converted into triglycerides. Triglycerides are forms of fats that can be stored in the body.
Triglycerides circulate throughout the body and some of them are absorbed by the cells for energy. The rest are stored in the adipose tissue. Saturated fats have different structures than unsaturated fats. This makes it easy for lots of molecules to be packed together at the same location. Because of this tight packaging, it is difficult for the body to break down saturated fats. When you consume more fat than what’s needed by the body, your adipose tissue starts building up and you start putting on weight.
The more saturated fat you keep consuming over the years, the higher will be your body fat percentage.
Getting Technical - How’s Iron Circulated In the Body?
Iron Absorption
A fraction of the ingested iron is absorbed by the body. It can vary from 5% to 35% depending on a few factors like the type of iron (heme or non-heme) and hepcidin levels. Hepcidin is secreted by liver cells and is a circulating peptide hormone that coordinates the use of iron.
Iron Circulation
Iron circulation in the body occurs with the help of a protein called transferrin. The iron laden transferrin binds to its receptor, which leads to the entry of iron into the cell. Iron is then transported to the cell’s mitochondria, where it is used to synthesize heme or iron-sulfur compounds.
Did You Know?
Many people assume that saturated fats are types of trans fat, which are the worst types of fats you can eat. Trans fat is a byproduct of the process called hydrogenation. This process helps increase the shelf life of cooking oils to preserve them for a longer time. Trans fat is commercially produced and has no health benefits at all.
Saturated fats are not commercially produced like trans fats.
These naturally occur in the foods you eat. When had in the right amounts, saturated fats are beneficial to the body and help absorb certain types of vitamins. When you limit your fat intake and make sure you pick unprocessed and fresh sources of saturated fats, saturated fats are not bad! They don’t deserve all the bad rap they have been getting so long!
The History Behind Saturated Fats
In the 1950s, heart diseases were the biggest cause of death in the United States. On September 24th, 1955, the US President Dwight D. Eisenhower had a massive heart attack. Though he recovered and went on to win a second term, this caused an alarm in the US.
Diet and unhealthy lifestyles were both blamed for the increase in cardiovascular problems. It was during this time that fats were largely researched upon.
During the 1950s, researchers found a relationship between hyperlipidemia and heart diseases. This added fuel to the fire.
From the 1950s to the early 1980s, studies conducted all around the world found a positive relationship between saturated fats, weight gain, and cardiovascular problems.
In 1980, the ‘Dietary Guidelines for Americans’ was released by the US Department of Health and Human Services and the US Department of Agriculture. It asked people to limit their consumption of saturated fats and cholesterol.
Since then saturated fats have had a bad reputation globally.
RDA of Saturated Fats
For an average American, the recommended intake of saturated fats should be less than 10% of the total caloric intake.
For instance, if you are on a 1500 calorie diet, just 150 calories have to come from saturated fats.
For those diagnosed with high cholesterol levels or those with existing heart conditions, the recommended intake of saturated fats has to be less than 7% of the daily caloric value.
In terms of weight, the Daily Value (DV) of saturated fats is 20 grams per day.
How Genes Influence Saturated Fat Requirements?
FTO Gene and Saturated Fat Metabolism
The FTO gene is a very popular gene related to obesity and weight gain. Certain variants of the FTO gene seem to worsen the effects of a saturated fat-based diet.
There are two SNPs of the FTO gene that relate saturated fat intake and weight gain.
rs9939609 of FTO Gene and Weight Gain Tendency On Saturated Fats Intake
The A allele of the rs9939609 SNP makes people gain more weight upon saturated fat intake. The T allele does not relate saturated fats and weight gain though.
rs1121980 of FTO Gene and Weight Gain Tendency On Saturated Fats Intake
Similarly, the A allele of the rs1121980 SNP causes weight gain with saturated fats intake while the T allele does not result in weight gain.
APOA2 Gene and Saturated Fat Metabolism
The APOA2 gene helps produce a protein called apolipoprotein A-II. This regulates fat metabolism and also helps in building HDL cholesterol in the body. A primary SNP of the APOA2 gene relates saturated fat intake and weight gain.
rs5082 of APOA2 Gene and Weight Gain Tendency On Saturated Fats Intake
The G allele of the rs5082 SNP is associated with obesity and individuals gain excess weight up on saturated fat intake. The A allele however is not associated with either obesity or weight gain relating to saturated fat intake.
STAT3 Gene and Saturated Fat Metabolism
The STAT3 gene produces a transcription factor that helps in controlling various other genes in the body. There is a link between variations in the STAT3 gene, saturated fat intake and obesity.
rs8069645 and rs744166 of STAT3 Gene and Weight Gain Tendency On Saturated Fats Intake
Men with the G allele of both these SNPs are likely to gain more weight with saturated fats intake. This can also lead to obesity. Those with the A allele are not affected by saturated fats.
rs1053005 and rs2293152 of STAT3 Gene and Weight Gain Tendency On Saturated Fats Intake
The C allele of both these SNPs can weight gain and obesity in men up on excess saturated fats consumption. This relationship is not found in those with the T allele.
Non-genetic Factors Relating To Saturated Fats And Weight Gain
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Higher caloric intake - Saturated fats have 9 calories per gram of fat. In comparison to fats, carbohydrates and proteins have about 4-5 calories per gram only. Because of this, it is easier to consume more calories with saturated fat intake, which can lead to weight gain.
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Fat storage - When you consume more fat than what’s needed for the body, excess fat is stored in the adipose tissues. When you consume excess saturated fats, your adipose tissue grows and you start putting on weight.
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Taste - Fatty foods are generally tastier. Think of buttery bacon, fried chicken, sweet pastries, or a big slice of cheesy pizza. They get addictive with time and this is another non-genetic factor that causes gradual weight gain.
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Food combinations - Most packaged foods/ takeaways/ restaurant meals are a mix of carbohydrates and saturated fats. While carbohydrates give the body the needed energy, the excess fat you consume is mostly not used. This gets stored in the body, leading to weight gain.
What Happens When You Do Not Consume Saturated Fats?
Fats are essential sources of nutrition. Fats help absorb and transport certain vitamins throughout the body. Fats also provide you with insulation when the temperature goes down and maintains cell membranes.
The right amounts of saturated fats help produce steroid hormones like testosterone and estrogen. Fats keep you fuller for a longer time and are used by the body as energy when you are glucose deprived.
While it is healthier to bring down your saturated fats intake, do not skip them altogether. Choose unprocessed and fresher saturated fats to enjoy their benefits.
Excess Saturated Fats And Weight Gain
When you consistently include excess saturated fats in your diet (more than 10% of your caloric intake), here are some of the problems it can cause.
- Increased LDL cholesterol levels
- increased levels of heart disease markers
- Weight gain and obesity
- Increased body fat
Recommendations For Healthy Saturated Fat Consumption To Prevent Weight Gain
- Make healthier food choices. Let your sources of saturated fats come from natural plant sources and unprocessed meat. Stay away from processed meat, deep fried goods and pastries and savories.
- Low fat dairy products have limited saturated fats and also provide you with essential vitamins and calcium.
- Choose healthier cooking methods like broiling, sauteing, boiling, steaming, and baking instead of deep frying and roasting.
- Opt for skinless chicken and fish over red meat.
- Fill up your plate with healthy fruits and vegetables and smaller portions of fat.
- Be calorie conscious. Count your caloric intake for the day to stay fit. Make sure most of your calories come from proteins, natural sources of fat, and complex carbohydrates.
- It is ok to treat yourself to fast foods and packaged goods once in a while. For the majority of the time, cook your meals fresh at home.
Summary
- There has been a constant debate on whether or not saturated fats are healthy for the human body.
- Saturated fats in limited quantities are not harmful but excess consumption of the same can increase LDL cholesterol levels and increase your risk for heart diseases and obesity.
- People looking to lose weight have to definitely keep a check on their saturated fat levels.
- Genetically, some people can gain excess weight with saturated fats intake when compared to others.
- Get your saturated fats from natural plant and animal sources and make sure you limit consumption to 10% of your total caloric intake.
Reference
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5642188/
https://www.health.harvard.edu/staying-healthy/new-thinking-on-saturated-fat
https://www.health.harvard.edu/staying-healthy/the-truth-about-fats-bad-and-good
https://pubmed.ncbi.nlm.nih.gov/20934605/
