Lipids, what are they?
Lipids play many roles, depending on their nature since we distinguish between storage lipids, structural lipids and functional lipids. Reserve lipids are located in adipose tissues and are mainly stored in the form of triglycerides. They constitute the main energy reservoir of our body. Adipose tissue has a thermal insulating role, meaning it helps maintain our body temperature.
Did you know ?
Triglycerides are fatty acids synthesized by the liver and the intestine, but can also be provided through food. A high blood triglyceride concentration is considered a cardiovascular risk factor.
The structural lipids make up the cell membrane and maintain its integrity to ensure intracellular exchanges. Functional lipids can be the vectors of fat-soluble vitamins (A, D, E and K) which allow their absorption and transport within the body. In addition to participating in the prevention of numerous pathologies (cardiovascular diseases, inflammatory diseases and cancers), they play an important role in the production of molecules essential to the body such as hormones. The metabolism of dietary lipids begins during their digestion and intestinal absorption. The lipid nutrients will be cut into smaller molecules by an enzyme which will release the fatty acids, later captured by the liver. The majority of circulating fatty acids are taken up by body fat and stored as triglycerides in adipose tissue. These constitute a significant and easily usable energy reserve.
What are the different fatty acids and in which foods can they be found?
Consuming fat is therefore crucial for the body, however some food sources are better than others.
Saturated fatty acids.
Saturated fatty acids are naturally produced by the liver, brain and adipose tissue, but are also provided through food. Saturated fatty acids are found in large quantities in butter, cream, cold meats, whole dairy products, cheese, meat, but also in palm, coconut and palm kernel oils. Saturated fatty acids can be classified into 3 categories according to their length: short, medium or long chains. Short and medium chain fatty acids will have a preventive role in the appearance of colon cancer. They are non-hypercholesterolemic, meaning they do not increase cholesterol levels and are not associated with the risk of cardiovascular disease. They are present in butter and cheeses. Long-chain saturated fatty acids are the major components of the myelin sheath (envelope covering neurons) in the cerebral nervous system. In excess, long-chain saturated fatty acids can have atherogenic (participate in the formation of lipid plaques on the arteries) and thrombogenic (participate in the formation of clots) effects and are hypocholesterolemic, i.e. they play a role in lowering blood cholesterol levels.
Unsaturated fatty acids.
There are two types of unsaturated fatty acids: monounsaturated and polyunsaturated.
Monounsaturated fatty acids.
Monounsaturated fatty acids or better known as omega 9 (oleic acid) are synthesized by the body and are also part of the composition of triglycerides. They play a preventive role in the onset of cardiovascular diseases. They are mainly found in olive oil, avocado and oilseeds (almonds, walnuts, etc.) but can also be present in certain products of animal origin such as duck fat.
Polyunsaturated fatty acids.
Polyunsaturated fatty acids are so-called essential fatty acids, because our body cannot synthesize them and are therefore necessarily provided by food. There are 2 types
1. Omega 3
Omega 3 are hypotriglyceride-lowering fatty acids (reducing triglyceride levels), anti-inflammatory, increase HDL-cholesterol (good cholesterol) while improving vision and participating in the prevention of neurodegenerative diseases. There are 3:
- alpha-linolenic acid (ALA): it is found in linseed and rapeseed oils and in nuts. This acid is the precursor of EPA and DHA. Based on an average energy requirement of 2000 kcal, it is recommended to consume 2.2 g of alpha-linolenic acid.
- eicosapentaenoic acid (EPA): this acid is an anti-inflammatory which helps protect the arteries and the heart. It also limits bone demineralization. The recommended nutritional intake for this acid is 250 mg/day.
- Docosahexaenoic acid (DHA): it is the main fatty acid present in the membranes of neurons. It plays a fundamental role in the development of the brain and vision. Just like the EPA; DHA plays a role in protecting the heart. The recommended nutritional intake for this acid is 250 mg/day.
Flax and hemp seeds, nuts and the oils obtained from them are particularly rich in omega 3, as are fatty fish. Omega 3 has a recognized protective effect on the cardiovascular system. DHA and EPA are mainly present in fatty fish such as herring, mackerel or sardines.
2. Omega 6.
-Omega 6 or linoleic acid are hypotriglyceridemic, contribute to maintaining the integrity of your epidermis, our immune defenses and promote optimal reproductive function. In excess, they can be inflammatory and increase the risk of cardiovascular disease, diabetes and obesity. The omega 6 found in corn, soy and sunflower oils are also considered “good fats” but in excess, they prevent the optimal use of omega 3. In today's diet, there is an excessive average intake of omega 6. However, the balance of the omega 6/omega 3 ratio is an important element for the proper functioning of our body. In this context, the omega 6/omega 3 ratio should be between 4 and 10, the ideal being 5. If the recommended daily intake of omega 3 is 2.7 g per day and the ratio should ideally be equal to 5, then you are advised to consume approximately 13.5 g of omega 6 per day. At Feed., we use quality sources of lipids such as rapeseed and sunflower oils, almonds, yellow flax seeds, etc.
It is therefore important not to demonize the foods you eat because they all have a role to play in your nutritional balance and your health. Foods that are initially considered “fatty” are not necessarily bad for you.
How much fat do you need?
ANSES recommends a daily lipid intake representing 35 to 40% of total energy intake (AET). These recommendations place a strong emphasis on the quality of lipids and not the quantity. Here are the recommended daily nutritional intakes for each type of fatty acids and based on an average energy requirement of 2000 kcal.
- Saturated fatty acids: <8% of the AET or 22 gr
- Monounsaturated fatty acids: 20% of the AET or 44 gr
- Polyunsaturated fatty acids including:
-> omega 6: 10% of the AET or 22 gr -> omega 3: 2% of the AET or 4.4 gr including: ->ALA: 1% of the AET or 2.2 g ->DHA and EPA: 0.12% of the AET or 250 mg each.
What fatty acids should be limited as much as possible?
It is recommended to consume a minimum amount of trans fatty acids in your diet. They increase the level of LDL cholesterol (bad cholesterol) and accelerate the process of manufacturing cholesterol in the arteries. In other words, these are fatty acids that are harmful to your health and that you are advised to avoid as much as possible. Trans fatty acids are obtained by cooking oils at too high a temperature, during the manufacture of refined oils or during a hydrogenation process used in the food industry to solidify the fatty substances used. Today, food brands are obliged to indicate the presence and quantity of trans fatty acids in the product.
Did you know ?
In Feed. products, you will not find any processed fatty acids.
When to consume fat during the day?
“Don’t eat fat in the evening, you will store it much more quickly!” This sentence is often repeated wrongly because it absolutely does not reflect the truth. What matters is the overall lipid intake over your day. Just like proteins and carbohydrates, it is important to distribute your fat consumption across all your meals: breakfast, lunch and dinner according to your needs.
Can you lose weight faster by removing fat from your diet?
Logically yes, removing lipids from your diet allows you to lose weight more quickly. In fact, 1g of lipid provides 9 kcal while carbohydrates and proteins only provide you with 4 kcal per gram. However, when you consume fat again, your body will store these new reserves. You therefore greatly increase your chances of regaining the weight you lost. It is important to understand that fats, like carbohydrates and proteins, are not fattening if consumed as needed. They are also absolutely essential to your body.
