Has World Health Organization provided nutrition/diet/exercise guidelines to strengthen the human immune system for better responding to COVID-19?

Question

Medical sciences is not my subject but my personal feeling is that:

• A strengthen immune system can better respond to viruses than a weak immune system.
• A balanced diet in combination with exercise and adequate sun-light exposure strengthens the human immune system.

Is any of the above assumptions questionable?

If not, shouldn't the WHO provide any such guidelines (aside the virus-spread elimination guidelines) to better shield people (mainly elder ones) against COVID-19 infection or negative-effects of it?

I have not heard of any such guidelines (at least in Europe), but if there are, can you please provide the corresponding links?

Answer 1

There are guidelines actually:

In the Campains section there are the following links:

Feeding babies and young children during the COVID-19 outbreak April 2020

Proper nutrition is vital in the first two years of a child's life. It helps to: - ensure healthy growth
- strengthen the immune system
- improve cognitive development
- Reduce the risk of getting ill with infectious and chronic
deseases.

Breastfeeding advice during COVID-19 March 2020

[...] Breastfeeding is particularly effective against infectious deseases because it strengthens the immune system by transfering atibodies from you

Nutrition for adults during COVID-19 March 2020

Eat a well-balenced diet everyday to get the vitamins, minerals, dietary fibre, protein and antioxidants your body needs to be healthier with a stronger immune system and to lower your risk of chronic illnesses and infectious deseases.

In the technical guidance section also:

Food and nutrition tips during self-quarantine

[...]Good nutrition is crucial for health, particularly in times when the immune system might need to fight back [...]Alcohol is not only a mind-altering and dependence-producing substance, harmful at any level consumed, but it also weakens the immune system

Stay physically active during self-quarantine

[...]Staying at home for prolonged periods of time can pose a significant challenge for remaining physically active. Sedentary behaviour and low levels of physical activity can have negative effects on the health, well-being and quality of life of individuals. Self-quarantine can also cause additional stress and challenge the mental health of citizens. Physical activity and relaxation techniques can be valuable tools to help you remain calm and continue to protect your health during this time.

WHO recommends 150 minutes of moderate-intensity or 75 minutes of vigorous-intensity physical activity per week, or a combination of both.[...]

Answer 2

Not sure about the WHO, but this article might help in Sports Medicine

The Challenge of Maintaining Metabolic Health During a Global Pandemic