Fats (lipids, fatty acids) are one of the three basic nutrients necessary for the proper functioning of the body.
Fats are a diverse group of organic compounds, which include: fatty acids, cholesterol, sterols, stanols, waxes, phospholipids.
Most fats in our diet are triglycerides, i.e. esters of glycerol and three fatty acid molecules (carbon, oxygen and hydrogen atoms); these are simple fats. Complex fats may additionally contain, for example, phosphorus, nitrogen and sulfur.
Fats are divided according to:
the structure of the molecule (simple fats and complex fats),
the origin of the fats (vegetable fats and animal fats),
the number of double bonds in the carbon chain (saturated fats and unsaturated fats),
the length of the chain (short-, medium- and long- chain),
the position of the first double bond (cis isomers and trans isomers).
Saturated fatty acids- SFA (saturated fatty acids)- do not form any double bonds and differ from each other in the number of carbon atoms in the chain.
Unsaturated fatty acids- UFA (unsaturated fatty acids)- are divided into monounsaturated and polyunsaturated acids.
Monounsaturated acids- MUFA (monounsaturated fatty acids)- are fat molecules with one unsaturated double bond.
Polyunsaturated fatty acids- PUFA (polyunsaturated fatty acids)- are fats containing more than one double bond.
Trans fatty acid isomers have a negative effect on the body, they should be completely eliminated from the diet, or should not exceed 1% of the energy in the diet:
they increase LDL concentration,
by lowering HDL concentration,
they increase the risk of cardiovascular disease,
they increase triglyceride concentration,
they have a pro-inflammatory effect,
they reduce the elasticity of cell membranes.
Saturated fatty acids are not unhealthy, but the body is able to synthesize them on its own; therefore, a healthy diet should be dominated by unsaturated fatty acids, which the body is unable to synthesize due to the lack of the appropriate enzyme.
1 g of fat is 9 kcal
The demand for fats depends on many factors, including: health, age, energy management status of the body, physical activity, physiological condition, gender.
Unsaturated fatty acids:
monounsaturated (monoenoic) acids- palmitoleic acid, erucic acid,
nervonic acid, oleic acid,
diounsaturated (dienoic) acids- linoleic acid,
triunsaturated (trienoic) acids- α-linolenic acid, γ-linolenic acid,
tetraunsaturated (tetraenoic) acids- arachidonic acid.
NNKT- essential unsaturated fatty acids, a group of highly unsaturated fatty acids containing 2-4 double bonds; they have unique physical and biological properties. The human body cannot synthesize these compounds due to the lack of appropriate enzymes- they must be supplied with food or supplementation, they are necessary for the proper functioning of the human body.
Polyunsaturated fatty acids are Omega acids
Omega 3 acids
α-linolenic acid (ALA),
eicosapentaenoic acid (EPA),
docosahexaenoic acid (DHA).
Omega 6 acids
linoleic acid (LA),
γ-linolenic acid (GLA),
arachidonic acid (AA).
EFAs in the human body:
are precursors of vitamins A, D, E, K,
cardioprotection (lower incidence of circulatory system diseases),
enable energy storage, constituting the body’s energy reserve,
support the circulatory system, reduce vascular tension, affect the reduction of blood pressure,
slow down the processes of formation of prothrombotic factors in the body, reduce the concentration of triglycerides,
anti-atherosclerotic effect,
have a building function,
participate in the synthesis of eicosanoid compounds exhibiting pro- and anti-inflammatory effects,
support brain function by affecting the nervous system,
produce hormones and bile acids,
influence the functioning of the immune system,
constitute the building material of cell membranes,
fulfill metabolic functions,
source of energy,
thermal function,
reduce the risk of arthritis and diseases of rheumatoid substrate, support calcium absorption,
preventive in relation to diseases of old age.
Symptoms of EFA deficiencies:
weakness, general fatigue,
problems with memory and concentration,
lowered immunity,
mood swings,
muscle cramps,
skin diseases.
Symptoms of EFA deficiency for the skin:
– dryness,
– irritation,
– skin dehydration,
– excessive keratinization,
– premature skin aging,
– loss of firmness and elasticity,
– skin peeling,
– increased allergic reactions and skin rashes,
– problems with healing and regeneration.
EFAs in cosmetology:
– prevent transepidermal water loss (TEWL) and help retain water in the epidermis,
– strengthen the functioning of the protective barrier of the epidermis, maintain hydrolipid balance,
– are a component of intercellular cement, participate in the synthesis of ceramides,
– play an important role in the metabolic processes of the skin,
– inhibit skin ageing processes,
– alleviate the symptoms of dermatoses such as psoriasis or atopic dermatitis,
– increase skin immunity, reduce susceptibility to irritation,
– accelerate regeneration and the healing process,
– antioxidant effects, strengthen anti-radical protection,
– regulate the process of exfoliation of the epidermis,
– participate in the production of collagen and elastin, affect the firmness and elasticity of the skin,
– alleviate the signs of oxidative stress,
– nourish, moisturise, regenerate,
– act anti-inflammatory,
– smooth the skin and make it soft,
– regulate the fluidity of the cell membrane structure.
Source of healthy fats
vegetable oils and butters with 80% fat content,
fish and seafood,
nuts, seeds and pits,
dairy products and eggs,
avocado.