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Coronavirus Q & A with Commercial Nutritionist Mark Gilbert

We’ve sat down with our Commercial Nutritionist Mark Gilbert to help answer some of the questions relating to Coronavirus

Q: Some people have said that low-calorie diets are bad for immunity, so what is the effect of calorie restriction on the risks associated with COVID-19?

A: The only honest answer to this question is that nobody knows for sure because Coronavirus (COVID-19) is not yet adequately understood, but what we can say is that multiple studies show improvements in immune function with calorie restriction.

Of the limited number of studies I could find, one showed obese people have a diminished immune response (this is why those with a BMI over 40 are considered ‘high risk’). It also showed that a nutritionally balanced, very low-calorie diet was shown to reverse this loss of immune function. Another study in overweight people showed that caloric restriction for six months, with a diet that contained the recommended intake of vitamins and minerals, improved the function of T cells. These are the body’s key immune cells that fight infection, including viruses.

However, nutritional deficiencies or malnutrition could have the opposite effect and might make a person more susceptible to infection. Also, once infected, metabolic rate may be increased, so those on a very low-calorie diet might want to increase their intake of nutritious foods, like protein, fruits and vegetables, for several days or weeks. This is what we recommend. If you experience mild symptoms (as with over 80% of coronavirus cases), Step 1b or above is recommended. If symptoms are more severe, we would advise that a dieter moves to Step 4 or higher.

Q: I’ve heard that certain vitamins, herbs and supplements may help to fend off Coronavirus or treat symptoms. Is this true?

Most statements about vitamins or supplements being able to ward off Coronavirus are untrue or misleading and should be treated with scepticism. We certainly don’t make this claim. Of course, most experts believe that a healthy, varied diet is likely to reduce the risk of contracting the disease or suffering the worst consequences of it. Unfortunately, nutrition surveys from the UK and USA show that the great majority of people are deficient in at least one vitamin or mineral. This is concerning because these nutrients are crucial to a healthy immune system.

In fact, a very recent research review on nutrition and immune function, which looked at 231 scientific studies, stated that, in the author’s words: “Vitamins A, D, C, E, B6, B12, folate, zinc, iron, copper, and selenium…play vital, often synergistic roles at every stage of the immune response”. This makes a strong case for either improving your diet or taking a quality multi-vitamin/mineral supplement. The daily requirement of these and all other essential nutrients are provided by three products by The 1:1 Diet by Cambridge Weight Plan range, so in that case, you wouldn’t need to add a multivitamin/mineral.

Q: What about fluids/hydration? Is it important to drink a lot?

A: An overview of the responses of a large group of patients infected by Coronavirus in China indicates that hydration can be crucial, as dehydration can cause the blood pressure to go dangerously low. The 1:1 Diet fluid intake recommendations are consistent with the British Nutrition Foundation recommendations of “6-8 mugs or large glasses a day”.

Q: Can Coronavirus be spread through food?

A: As of 21st March, most government agencies and health authorities are reporting that there is currently no evidence that the virus can be spread in foods. However, ANSES (France’s Health & Safety Agency) says this could be a risk. Also, some experts have suggested food-borne transfer of the virus is possible. Thorough cooking is likely to kill the vast majority of any virus that was present in food and you should ensure that you thoroughly wash any fresh produce before eating. If restaurants and takeaways follow the rules on food preparation, risk should be very low and of course, the products from food manufacturers, like ourselves, who follow the strictest food safety protocols, designed to eliminate microorganisms, are very low risk.

If you want to find out more about how The 1:1 Diet has adapted to the coronavirus outbreak, visit How does COVID-19 affect me on The 1:1 Diet?

To find out more about being on Plan and how to start your weight loss journey, speak to a Consultant today!