Are Saturated or Unsaturated Fats Better For Your Health?
The internet has made information possible and easily accessible for consumers, it has also led to a rise in confusion regarding nutrition and balanced dietary intake requirements for individuals of all ages.
The most common example is spreading misleading information between nutritionist and consumers on the overall avoidance of dietary fat by consumers.
For many years consumers reduce the fat intake in foods due to high density of lipids as the main aim was to reduce calorie intake.
As a result, reduced fat and increased carbohydrate foods were suggested in order to reduce cardiovascular diseases and weight loss.
However, this recommendation led to the intake of refined carbohydrate diets by consumers with added sugars and with the result avoidance of high nutrient foods which were abundant in saturated fats like oilseeds, and fruits such as avocado were prevalent.
Therefore intake of fat has lowered and carbohydrate ingestion has increased resulting in high calories therefore increasing obesity chances in individuals.
Saturated fats increase the risk of cardiovascular disease and certain cancers, whereas unsaturated fats lower the risk of these conditions.
It is hard to know what healthy fats to eat. Numerous recent studies have focused on how good and bad fats affect our health.
In this article, we will look at dietary fats, the types, sources, their benefits for human consumption and impacts on human health.
What are Dietary Fats?
Dietary fats also known as lipids are mainly triglycerides composed of fatty acids with varying chain length, which may be saturated, monounsaturated or polyunsaturated.
The relative proportions of saturated and polyunsaturated fatty acids in the diet may be of primary importance in determining their nutritional implications.
In diets very low in fats, phospholioids may constitute a relatively high proportion of the fat since they are a component of vegetable and animal cells.
Why You Need Dietary Fats?
Among the three macronutrients, that is carbohydrates, proteins, and fats, the latter, mainly composed of fatty acids part of triglycerides and to a lesser extent, phospholipids are important for your health.
Humans also ingest glycolipids, other complex lipids, and cholesterol. In many developing countries, fat intake is increasing, while in developed countries, fat intake has tended to decline over the past 30 years.
Fats are quantitatively relevant in the diet because of at least two reasons:
- Easy availability due to massive cultivation of plants for oil production
- Current low cost of energy-rich fatty foods
We also need to eat dietary fat for:
- Essential fatty acid intake
- Liposoluble vitamins intake
- Augment food palatability
What are the types of dietary fats?
The are two types of dietary fats, namely; Saturated fats and Unsaturated fats.
Saturated fats are fatty acids with longchain hydrocarbons containing single bonds, they are solid at room temperature, where as Unsaturated fats are fatty acids with one or more double bonds in a long hydrocarbon chain and are liquid at room temperature, both have the carboxyl group (-RCOOH) present in their structures.
Saturated fats can be found in:
- Cow meat
Unsaturated fats sources:
- Olive oil
- Corn oil
- Flaxseed oil
- Canola oil
Are saturated or unsaturated fats good for human health?
Fats have always been linked with the increased cardiovascular diseases, and cholesterol has always been thought as a major reason for cardiac arrest, this is because of the increase in the serum of the total cholesterol level and the LDL cholesterol in the body.
Factors responsible for cardiovascular diseases are:
Do unsaturated fats cause more problems than saturated?
The dietary intake of saturated fatty acids is important in determining plasma LDL cholesterol levels. This class of fatty acids has long been considered as positively associated with cardiovascular risk.
The debate is still going on, but the consensus that saturated fat consumption must be limited is slowly fading away. Analysis reported that there was no association between saturated fat intake and overall mortality. The critical issue is that an unrestricted reduction of saturated fats leads to the ban of otherwise healthy food, such as dairy foods.
In a study, nondiabetic patients consumed diets that contained either 60% of total calories from carbohydrate or 40% carbohydrate.
The 60% carbohydrate diet resulted in higher fasting plasma triacylglycerol, small amounts of lipoprotein, traces of lipoprotein triacylglycerol, and lower HDL cholesterol without changing LDL cholesterol concentrations.
These diets were consumed in random order for two weeks, with a two-weeks washout period between them.
The effect of the low-fat diet was not limited to higher fasting plasma triacylglycerol and lower HDL cholesterol, but also included a persistent elevation in the remaining lipoproteins. These findings led to question whether it is wise to recommend that all Americans replace dietary saturated fat with carbohydrate.
Nutrition scientist went on further to investigate more by looking at diets containing monounsaturated and polyunsaturated fatty acids.
In a recent study, relations between fatty acids intake and metabolic syndrome status among overweight and obese women were addressed.
Overweight women with metabolic syndrome consumed higher amounts of monounsaturated fat, polyunsaturated fat, and linoleic acid compared to overweight women without metabolic syndrome.
Further, in a large sample of swedish middle-aged men, a follow-up of 32 years showed that raised amounts of palmitic, palmitoleic, and oleic acid were related to a higher risk for stroke attacks, whereas a higher proportion of linoleic acid was protective.
Further studies on diets containing omega-3 and omega-6 polyunsaturated fatty acids were also done to compare which one will be most suitable for replacing saturated fats. Research on linoleic acid gained traction when this fatty acid was shown to decrease blood cholesterol levels.
The public health authorities adviced that consumers should add polyunsaturated fats with linoleic acid in their diet.
Indeed, polyunsaturated fat in the USA increased from approximately 3% of energy to about 6–7% of energy. The increase in linoleic acid consumption led to a 50% reduction of cardiovascular disease in the US. This profound dietary change was confirmed by large increases in the linoleic acid content of adipose samples.
The effects of omega-6 polyunsaturated fatty acids on blood lipids were calculated by equations that yielded almost the same results, meaning consumption of saturated fat is positively related, and polyunsaturated fat is inversely related to serum cholesterol levels.
In summary, compared to carbohydrates, polyunsaturated fats reduces low-density lipoproteins with little effect on HDL cholesterol and triglycerides.
Thus, dietary intake of omega-6 fatty acids, the substitution of 5% of calories from saturates with linoleic acid was associated with a reduction in cardiovascular risk in the USA.
Omega-3 fatty acids, especially those which are most relevant, the eicosapentaenoic and docosahexaenoic acid have become similar to micronutrients.
A strong evidence shows that an adequate dietary intake of omega-3 from plant foods such as linseed, canola, soybean oils and walnuts, namely alpha-linolenic acid, and from fish containing EPA and DHA is associated with significant reduction of coronary risk and sudden death.
Dietary fats are mainly triglycerides of fatty acids, which may be saturated, monounsaturated or polyunsaturated, and they all have great health benefits.
Though fats contains high amounts of lipids and provides energy for the body some can contribute to cardiovascular diseases.
Consumers must be cautious of the amounts of saturated fats intake, and replace them with polyunsaturated fats in their diets, most escpecially omega-3 and omega-6 fatty acids.
They must also adhere to nutritional guidelines and dietary restrictions on any food they buy from shops.