The flu diet is a diet that - while not able to directly cure the disease - helps support the body in fighting the infection.
For disclosure correctness, we remind you that the flu is a viral pathology and that, therefore, the use of antibiotics is totally inappropriate (except for secondary complications).
Influenza means an infectious disease caused by viruses belonging to the Orthomyxoviridae family.
Flu symptoms are mainly: fever, pharyngitis, nasal and sinus congestion, muscle and bone pain, headache and cough.
Sometimes, the flu also induces nausea and vomiting, especially in young people.
Serious complications - such as pneumonia, exacerbation of asthma and worsening of heart failure - are quite rare, affecting mainly the elderly, immune-deficient subjects and those potentially at risk.
What does the diet have to do with it?
While not directly intervening in the elimination of the pathogen, the diet for the flu has an irreproachable importance on the speed and effectiveness of healing.
An appropriate diet is in fact able to reduce the negative effects secondary to fever, nausea, vomiting and diarrhea, responsible for the tendency to dehydration, anorexia and nutritional malabsorption.
Fever is an immune response triggered by certain cytokines on the hypothalamic regulation center, which causes the body temperature to rise to accelerate the healing process.
Fever is therefore indispensable in the fight against the flu; for this, it should be reduced with drugs only when it becomes intolerable for the subject.
As anticipated, fever is caused by an increase in temperature by the body itself; since it is an active reaction, fever also has a more or less important energy cost, depending on the entity.
It has been estimated that increasing body temperature above 37 ° C can increase the basal metabolic rate by up to 13%; however, considering that the flu causes a significant reduction in physical activity, the total calorie requirement does not increase as much as one might expect (for more information, see the Diet and Fever article).
One of the fundamental and unexceptionable aspects of fever is the increase in sweating; this, which is extremely variable between the various cases, determines a significant increase in water and salt requirements.
Nausea is a sensation of discomfort and discomfort localized in the upper portion of the stomach, which very often results in the effect of involuntary vomiting.
Nausea is associated with reduced appetite up to anorexia and, if continued over time, becomes a very debilitating (undernutrition) and disabling symptom.
It was decided to differentiate vomiting from nausea for the different effect they can have on the subject's nutritional status, but not only.
As anticipated, vomiting is a frequent consequence of the feeling of nausea; however, the two circumstances can also reveal themselves in a totally independent way.
Especially in young subjects, and especially in the immediate post-incubation period, vomiting can occur without any kind of warning.
While nausea has a secondary negative nutritional effect (loss of appetite and anorexia), vomiting is responsible for both a nutritional loss (of the expelled meal) and a loss of liquids (digestive juices of the stomach, small intestine and major glands) .
Among the short-term consequences of vomiting, the most significant are malnutrition and dehydration.
Like vomiting, diarrhea or dysentery is also a symptom that occurs mainly in young people and that can give rise to more than significant complications.
Diarrhea has a rather pronounced anti-nutritional effect, drastically limiting intestinal absorption and above all the reabsorption of water, mineral salts and vitamins in the colon. Sometimes, it is associated with mucosal flaking and bleeding, with further loss of water and increased nutritional demand.
The most significant effects are once again malnutrition and dehydration.
Diet and Advice
The basic principles of the flu diet are varied and very important but - depending on the specific case, the stage of the disease and the predominant symptoms - they can be slightly different.
In all types of flu, it is strictly advisable to ensure a high level of hydration, necessary to compensate for: sweating, increased hepato-renal function for the disposal of endogenous and pharmacological catabolites, any vomiting and diarrhea.
Body water can be maintained drinking more and eating liquid or well-hydrated foods.
However, if the flu is characterized by significant nausea and vomiting, this can become a serious problem. In such a case, the increase in liquid drinks and food becomes impractical, as the urge to vomit would increase dramatically.
Not everyone knows that the sense of nausea and vomiting are significantly worsened by some factors such as: fasting and hypoglycemia, gastric hyperacidity and excess fluid in the stomach.
Here is explained why, in case of intense nausea and vomiting, it becomes absolutely necessary to eat food:
- Highly pleasant (to counteract nausea, loss of appetite and anorexia), but always within the limits of the indications that will follow
- Dry or in any case not brothy, so that they tend to absorb gastric fluids rather than increase their volume
- Easy to digest, therefore: moderately protein but rich in essential amino acids (few peptides but with high biological value), low in fat and mainly unsaturated (lean foods and poor seasoning, only with raw vegetable oils), and possibly rich in carbohydrates.
In case of diarrhea, it is advisable that the following also result:
- Without mucosal irritating molecules (alcohol, other nerves, spices, etc.)
- Without osmotic agents, such as some sweeteners (xylitol etc.)
- Low in fiber.
This very first phase must be continued until the vomiting is reduced but never for too long; it is absolutely crucial to restore the supply of water and essential nutrients as soon as possible and, if necessary, by drinking from a soup spoon.
In patients at risk, dehydration is sometimes counteracted early with the use of IV bags (parenteral route).
Once the tolerance of liquids has been ensured, especially in children and always in the case of pharmacological use, it will be possible and desirable to use formulas for restoring the hydrosaline and alkaline balance such as Pedialyte, Milupa, Biochetasi etc.
In case of persistent diarrhea, this can be combated by taking natural products such as diosmectite and vegetable charcoal.
Milk and derivatives, with the exception of small portions of parmesan cheese on first courses, must be taken after at least 3-4 hours after taking tetracyclines by mouth, as they could inactivate the drug causing it to precipitate in the intestine.
When to start eating solid foods
The food insertion order more or less respects the following order:
water and rehydrating liquids → fruit jams and jellies → vegetable puree → pasta or rice in broth → lean veal, chicken and scaly fish, possibly blended to increase digestibility.
On the contrary, it is better to delay the intake of foods that are very fatty, raw or overcooked, or rich in connective tissue (shellfish).
We have already said that, as a rule, the flu does not cause an increase in energy needs; however, it is still uncertain whether it may require higher levels of other irreplaceable nutrients such as fatty acids and essential amino acids, vitamins and minerals.
When in doubt, once digestive capacity is guaranteed, levels of all useful nutrients should be increased, either through diet or supplements.
In particular, it is recommended to increase the vitamin ration by:
- Vitamin C or ascorbic acid, involved in the production of interferon (natural antiviral)
- Vitamins of the B complex, involved in the proper functioning of the immune system.
Other articles on 'Flu Diet'
- Flu Drugs
- Influenza - Herbal medicine
- Nutrition, Herbal Medicine and Flu
- Influenza vaccine