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Allergies vs the Cold vs Coronavirus vs Flu?



Allergies vs the Cold vs Coronavirus vs Flu?

How to Identify the Symptoms and use the Best Strategies and Supplements.


[Article References]


Before exploring what science tells us about how to handle a cold or flu, we need to better understand the difference between the cold, coronavirus, and the flu.


What is the Difference Between Allergies, Cold, Coronavirus, and the Flu?

allergiesThe Common Cold

The common cold typically causes head symptoms, along with a mild-to-moderate phlegm-producing cough

When one has a cold, they will commonly experience a stuffy, runny nose, sneezing, along with congestion.

The Flu (Influenza A or B)

Flu symptoms happen 1 to 4 days after infection, with a sudden onset, with a milder to a moderate and dry cough.

The flu is more often associated with body aches, chills, headache, and loss of appetite compared to COVID-19.

Coronavirus (COVID-19)

With a much longer incubation period and a gradual symptom onset, COVID-19 more often causes respiratory complications and shortness of breath versus the flu.

COVID-19 symptoms typically take 5 days, within a range of 2 to 14 days, with more severe and pervasive dry cough.

Seasonal Allergies

Occurring in the Spring, seasonal allergies are affected by one’s surrounding environment.

*** (Allergies, cold, and flu can aggravate asthma, which can lead to shortness of breath. The coronavirus can lead to shortness of breath on its own.)

Flu Symptoms vs Coronavirus Symptoms

allergiesCOVID-19 symptoms, less common with the flu:

  • Runny/ stuffy nose
  • Shaking with chills
  • Shortness of breath/ difficulty breathing
  • Sore throat
  • Sudden loss of taste or smell

*Symptom combinations — COVID-19 possibility comes with two or more symptoms present, while any single common flu symptoms are an indicator of the flu.

[Related Article: Are You Ready for COVID-19?]

[Related Article: How to Block Viruses with Zinc and Zinc Ionophores]

[Related Article: The Top 9 Science-Backed Immune System Supplements]


What is the Common Cold?

Generally self-diagnosable, the common cold is caused by viruses that will pass with a healthy immune system.

The symptoms of the cold are not caused by the infection, and instead, our body’s immune system fights it off.

Colds produce a mild-to-moderate cough with phlegm, along with aches, fatigue, and fever being mild and rare.


How Long Does the Cold Last?


With a gradual onset, the cold lasts 7 to 10 days.


How Long Are You Contagious with the Common Cold?


The cold is contagious 1 to 2 days prior to symptoms and lasts 5 to 7 days after presenting symptoms.

One is contagious with the cold as long as symptoms are present, sometimes up to 2 weeks.


What is the Cause of the Common Cold?


The cold is caused by over 200 different viruses, with 100 different human rhinoviruses (HRVs) producing about one-third of colds.


What are the Symptoms of the Cold?


The symptoms of the common cold are typically above the neck.


  • Aches and pains (mild)
  • Nasal congestion and postnasal drip
  • Runny/ stuffy nose
  • Sneezing
  • Sinus pressure
  • Sore throat (Usually the first symptom)
  • Watery, itchy, red eyes
  • Cough (mild to moderate with phlegm)


  • Body aches
  • Fatigue (mild)
  • Fever (mild, short, and rare)
  • Headache (rare)


When Should I go to the Doctor for the Cold?


Always seek medical attention when you have a fever exceeding 101.3°F, breathing complications, persistent fever, and sore throat, or prolonging sinus pain, or headaches.

If a child is experiencing a fever greater than 100.4°F, cold symptoms greater than 3 weeks, or extensively severe symptoms, they also need medical attention.


What is the Flu (Influenza)

The flu, or seasonal influenza, is a common respiratory infection caused by a virus affecting our lungs, nose, and throat.

How Long Does the Flu Last?


With a fast and furious onset, the flu can last from 5 to 7 days.

How Long Are You Contagious with the Flu?


Most are contagious with the flu for about 1 day prior to symptoms.

Older adults and children seem to be most contagious during the initial 3 to 4 days, remaining contagious for about 7 days.

Those with weak immune systems, including babies and the elderly, can be contagious for longer durations.

What are the Symptoms of Flu?



  • Aches and pains
  • Cough (typically dry)
  • Fever
  • Headaches


  • Diarrhea (with children)
  • Fatigue
  • Runny/ stuffy nose
  • Shortness of breath/ breathing difficulty
  • Sore throat (sometimes)

When Should I go to the Doctor for the Flu?


We should take children to the emergency room for flu symptoms when they experience rapid breathing or difficulty breathing, bluish skin, fever, rash, become unresponsive, or are not consuming fluids.

The CDC also recommends that one should go to the ER, when their flu symptoms ease and then return, especially with fever and coughs.


What is COVID-19/ Coronavirus?

allergiesCOVID-19 is a respiratory disease caused by a new coronavirus strain, SARS-CoV-2

Four other coronavirus strains are common to humans, all of which cause cold-like symptoms.

Some of what we know about the virus remains under further investigation.


How Long Does the COVID-19/ Coronavirus Last?


The average duration of illness is about 2 weeks after initial symptoms, with more severe cases lasting 3 to 6 weeks.

While symptoms can begin in as little as 2 days after infection, they usually begin after 4 days and can take up to 14 days to occur.

Unlike the flu with a rapid onset, the disease progression is more similar to the common cold, with a gradual onset.

How Long Are You Contagious with COVID-19/ Coronavirus?


It’s possible for one to spread the virus for 2 days prior to symptoms while being contagious for 10 days after symptoms present themselves.

When one is asymptomatic or after symptoms resolve themselves, they can remain contagious for 10 days after a positive COVID-19 test.


What are the Symptoms of COVID-19/ Coronavirus?



  • Fatigue
  • Fever
  • Cough (usually dry)
  • Shortness of breath/ breathing difficulty

Less Common

  • Aches and pains
  • Chills
  • Diarrhea
  • Headache
  • Loss of smell/ taste
  • Runny/ stuffy nose
  • Sore throat

*Upper respiratory symptoms associated with the common cold, such as a runny/ stuffy nose and sinus congestion, are uncommon in COVID-19, whereas they are common with the cold.


When Should I go to the Doctor for COVID-19/ Coronavirus?


According to the CDC, if symptoms worsen, becoming severe, one should seek medical attention.

This includes difficulty breathing, prolonged pressure and, or pain in the chest, confusion, inability to stay awake, or bluish face or lips.


What are Allergies?

allergiesNasal issues such as a runny nose can occur when spring arrives.

This could indicate a cold, but also one could be experiencing seasonal allergies, which can occur with the seasons or year-round.

Airborne pollen from an array of plants is the most common allergy cause in the spring.

Pollen is nearly invisible to the eye but can wreak havoc on your body’s immune system.

Our body’s immune system releasing antibodies to fight off these allergens.

This releases histamines triggering symptoms such as itchy eyes or runny nose.

These allergy symptoms can be increased with high pollen counts on windy days.

  • Cough
  • Fatigue (less common)
  • Headaches less common)
  • Itchy nose, eyes, throat, sinuses, and ear canals
  • Runny or stuffy nose
  • Shortness of breath
  • Sneezing
  • Watery eyes

[Related Article: Histamines: Friend or Foe? DAO and Beyond]


The Top Science-Backed Supplements for the Cold and Flu


This article will focus on the top science-backed supplements and strategies for beating the cold and flu.

For supplements and strategies on seasonal allergies and the coronavirus, please see the links above.


#1 Vitamin D

Vitamin D is the rising supplement star of 2020, as the data suggests sufficient vitamin D levels can be protective against acute respiratory tract infections.

Increasingly, we recognize vitamin D affects how much of the virus enters cells, while also regulating the effects on our inflammatory response.

We can associate low vitamin D levels with worsening immune function and increasing acute respiratory infection rates.

It is well-documented low vitamin D levels across countries with lower sunlight levels, and genetically levels are both associated with increased rates of acute respiratory tract infections.

A recent meta-analysis of double-blind placebo-controlled studies involving over 11,000 participants, worldwide and across diverse demographics shows people with deficient vitamin D levels experience an 18–60% reduction of risk in acute respiratory tract infections when taking vitamin D supplements at the onset of symptoms.

Those with adequate vitamin D levels get a lower benefit with a 0–23% reduction of risk in developing an acute respiratory tract infection.

We can estimate every hour of direct UV sunlight exposure can raise vitamin D levels 10 ng/ mL, the equivalent of taking 1,000 IU in the oral form.

Some such as the elderly and those with inflammatory conditions and metabolic disease may need higher vitamin D levels.

Dosage Details:

Sufficient magnesium, another common micronutrient deficiency is needed to absorb oral vitamin D. A good daily option is a vitamin D3 supplement including vitamin K2. Vitamin K is needed with higher doses of vitamin D. Many are now suggesting taking 5,000 IU of vitamin D daily, with some even taking as much as 10,000 IU of vitamin D.


#2 Zinc

Required for the development and growth of cells that manage our immune response, zinc is also an essential structural enzyme and protein component needed for healthy immune function.

Supporting our immune system against infections, zinc is a mineral that can inhibit viral replication in our nasal epithelium, along with lowering inflammation of the respiratory tract.

Superoxide dismutase, a zinc-containing antioxidant enzyme, protects our immune cells from reactive oxygen species, (ROS), as they are produced to destroy pathogens during our immune response.

Cell studies show zinc can inhibit rhinovirus attachment within the nasal cavity lining while slowing respiratory viruses replication in the body.

Zinc acetate or gluconate lozenges taken within 24 hours of symptoms can lower the duration and severity of symptoms.

Readily dissolving and releasing localized zinc ions, zinc acetate and gluconate lozenges can support the throat and nasal cavity in fending off infections.

George Eby holds a USPTO patent for zinc lozenges as the cure for the common cold.

Zinc can cause major organ distress, so we should only use high doses as needed, with up to 180 mg doses found safe for 1 to 2 weeks of use.

Nasal sprays, swabs, and zinc gels do not have proven benefits while carrying risks of permanent or temporary loss of smell and taste.

Dosage Details:

For prevention, a high-quality two-a-day multivitamin and along with dietary zinc is the best strategy. Higher zinc doses can harm the kidneys and liver. For best results, beginning within 24 hours of initial symptoms, sucking on and not chewing zinc lozenges every 1 to 3 hours can provide significant symptom relief.

If one develops severe side effects, such as severe headache or stomachache, as they should discontinue use. One should avoid additives containing formulations such as certain amino acids, citric acid, and magnesium stearate which can worsen cold symptoms.


#3 Pelargonium Sidoides

Containing prodelphinidins, which can block pathogens attaching to the throat and lungs Pelargonium sidoides, is a plant we know as umckaloabo or South African geranium.

With fewer studies on the cold and flu, Pelargonium sidoides has been historically used in the treatment of acute bronchitis.

One human study displays the potent anti-cold and anti-influenza effects of Pelargonium sidoides.

With dry and hoarse coughing symptoms, Pelargonium sidoides can lower the severity and duration of these symptoms, when taken at initial onset.

We see two times the symptom reduction, and over two times the rate of cure, in those taking elderberry.

While Pelargonium sidoides is effective in treating infections, it does not appear to prevent the occurrence of infections.

Dosage Details:

Pelargonium sidoides studies use EPs 7630, a patented 8 to 10:1 extract. A 7630 syrup is also available as taken by ¼ teaspoon, three times daily in research studies. Another option is EPs 7630 hydroalcoholic extract at 1 teaspoon, three times daily. In the powder form, 720 mg taken three times daily is used.


#4 Elderberry

allergiesElderberries, (Sambucus nigra) are a popular medicinal adaptogenic plant widely used in Egyptian, Mediterranean, and Native American cultures.

Animal as well as human cellular studies showcase the antiviral properties of elderberries, most specifically inhibiting influenza, the flu.

While human studies were not well-designed, we find consistent results across them showing elderberry supplementation within 24 hours of initial symptoms leads to mild-to-moderate flu outcomes.

With the rise of the coronavirus, we have witnessed some warnings that elderberries could further complicate a cytokine storm.

These warnings are based on a single elderberry supplementation study exhibiting cytokine effects, with cytokines being a critical and natural immune system response.

While more applicable to the coronavirus, in severe flu cases, cytokine storms can promote lung inflammation, and sometimes death.

As a cytokine storm is a severe immune overreaction to invading pathogens, the article outlines how Sambucol Elderberry antiviral properties can activate a healthy immune system through increasing inflammatory cytokine production.

While it would seem improbable low to even moderate elderberry use could promote a

cytokine storm, it is unclear if large elderberry doses during severe symptoms could cause adverse outcomes.

As always, one should always discuss supplement use with their physician.

Limited evidence leads us to believe taking elderberry as a short-term preventative measure might lower the risk of a cold.

Dosage Details:

Do not use raw elderberries because of their toxicity. Take elderberry when symptoms arrive and continue until resolved. Popular flu products add elderberry to zinc lozenges and appear to be a good option.

Elderberry is also available in capsules, with 700 to 900 mg of elderberry extract used in 3 to 4 divided doses. In Sambucol syrup form, study participants take 1 teaspoon (5 mL) four to five times daily.


#5 Vitamin C

allergiesAs a water-soluble essential vitamin, vitamin C, or L-ascorbic acid is a popular dietary supplement because of its antioxidant properties, safety, and low price.

Able to act as an antioxidant and pro-oxidant, depending on the body’s needs, vitamin C is a versatile vitamin.

As vitamin C isolates free radicals, its levels are restored by antioxidant enzymes.

Our immune cells produce reactive oxygen species, (ROS), to eliminate pathogens, while vitamin C protects these cells from pathogenic damage.

While the evidence does not appear to show basic vitamin C lowering cold and flu frequency in a healthy population in past studies, it is clear vitamin C lowers symptoms of the cold by 8–14%, depending on the age, for all when taken at the beginning of a cold, or for ongoing preventative measures.

These benefits increase to 50% for athletes and those under physical stress or individuals with insufficient vitamin C levels.

This leads us to investigate whether a high dose or mega dosing of vitamin C can be more effective.

Many suggest megadosing vitamin C between 5 to 10 grams is more effective.

One study shows those taking 1 gram vitamin C hourly for the first 6 hours, and three times daily could effectively relieve and prevent cold and flu symptoms.

Observational cancer studies show greater benefits of vitamin C administered intravenously, while newer vitamin C formulations are in liposomal form for greater bioavailability.

For those who suffer from allergies, vitamin C can lower histamine levels by directly removing the histamine molecule.

Dosage Details:

For basic coverage 1 to 2 grams of vitamin C, L-ascorbic acid in divided daily doses. Choosing vitamin C in a non-GMO form can make sense. It is unclear whether a high dose of vitamin C can cause kidney stones. One recent study shows in 2% of participants, and those predisposed to kidney stones, experiencing kidney stones with a high dose of vitamin C. If one has a history of kidney stones, they can consider not exceeding 1 gram of vitamin C daily.

According to the Linus Pauling Institute, little scientific evidence supports any type of oral vitamin C being better absorbed over others. As the debate continues over “natural” vitamin C versus L-ascorbic acid, they further assert there is no difference in the effects of “natural” vitamin C and L-ascorbic acid.


Top 10 Notable Cold and Flu Supplements

Oregano Oil

Cell studies show oregano oil delivers potent antiviral activity, as it has traditionally been a plant for fever and respiratory symptoms.

Carvacrol from oregano is more effective on certain viruses, while oregano oil performs more effectively against respiratory viruses, including the flu.


Multivitamin/ Mineral

An array of vitamins and minerals such as vitamins A and E, selenium, and iodine, and many more can help support the immune system and immune response.

Taking a quality two-a-day can help cover basic micronutrient needs.


Zinc Ionophores

Black seed oil, green tea, quinine, stinging nettle, cinchona, and quercetin have been shown to possess zinc ionophore actions.

This means they can transport zinc into the cells, allowing it to help the immune system fight off infection.



It is a potent scavenger against the coronavirus in multiple studies.

Protective against viral infections, melatonin appears to be a cold and flu supplement to consider.


Pterostilbene (Other Polyphenols)

Pterostilbene, a natural blueberry compound, is arguably one of the strongest and best-absorbed polyphenols.

Recent research suggests it might be effective against respiratory viruses.



Garlic presents itself as a promising cold and flu preventative supplement through increasing the availability of white blood cells.

Whether raw or aged garlic extracts, this supplement is one to consider for those who are often sick as its clinical value appears to be prevention and not the improvement of symptoms once sick.


Medicinal Mushrooms: (Chaga, Cordyceps, Lion’s Mane, Maitake, Reishi, Shitake)

The top medicinal mushrooms show strong actions to support the immune system’s actions.

We will await more studies for a better understanding of the dose and other factors.



In a head-to-head comparison, astragalus in one study more notably activates T-cells above the more well-studied echinacea.

The study used 1.23 grams of daily astragalus.


Bee Products: (Raw Honey, Manuka Honey, Pollen, Propolis, Royal Jelly)

Bee products also might be a valuable tool in immune support.

Some studies show the immune protection from these various different bee byproducts.



Echinacea shows antiviral activity in cell studies against viruses that have membranes, such as the rhinovirus, herpes simplex, influenza A and B, coronavirus (previous strains), and respiratory syncytial virus.

There are more than 10 echinacea studies on the common cold with mixed and inconsistent small symptom reductions along with unclear effective doses, active compounds, or even which symptoms are lowered.


Other Cold and Flu Supplements


NAC, spirulina, chlorella, ginger, glutamine, stinging nettle, quercetin, turmeric, cloves, (eucalyptus, peppermint, and rosemary essential oils), acacia fiber, acai berry, alpha-lipoic acid, Ang 1–7, Andrographis paniculata, berberine; (barberry, Bidens pilosa, goldenseal, Oregon grape root), boneset, chickweed, cinnamon, cordyceps, curcumin, red sage (dan shen), Dong Quai, frankincense, ginkgo Biloba, hawthorn, hesperidin, hesperetin, honeysuckle. Horse chestnut, Korean red Panax ginseng, kudzu, noni leaf, oats, oat fiber, olive oil, olive leaf, prebiotics, probiotics, psyllium fiber, red root, resveratrol, reishi mushroom, rosmarinic acid, rosemary, soluble fiber, weeping forsythia, Chinese skullcap, Japanese knotweed, licorice root, Rhodiola Rosea.


Conclusions on Cold and Cough Remedies

Public health officials agree, children below the age of 5 should not be given cold medicine, while children under 6 months old should only be given acetaminophen, and not ibuprofen or aspirin.

Cough and cold medicines will not prevent or shorten sickness but could provide some symptom relief.

Saline nasal drops and sprays can help with stuffiness and congestion.

Saltwater gargle, throats sprays, and lozenges can relieve sore throats.

Receiving plenty of rest and fluids is important.

Many advocate drinking warm liquids and honey, while others advocate using saunas and heat therapy.

A vaporizer or humidifier might provide additional relief.

The following is what I do when I feel a sickness coming on, as I try to respond immediately, staying on this protocol for several days.

Vitamin C: 1 gram every 30 minutes, watching for stomach rumbling.

Vitamin D3/ K2: 40,000 IU, and sometimes much higher.

Multi-vitamin: a high-quality 2-a-day complete vitamin.

Extra magnesium: magnesium is needed to efficiently absorb oral vitamin D3.

Zinc lozenges: 200 mg for 3 days. If it is the flu, then I’ll use zinc with elderberry lozenges.

Zinc Ionophores: black seed oil, cinchona bark, (restless legs the OTC med), green or matcha tea, quercetin are all options. I typically use matcha tea.

Melatonin: 40 mg at bed. Works well with vitamin C.

Heat therapy: I’ll take plenty of infrared saunas and hot showers while avoiding cold exposure. UV sunlight can help as well.

With heavy fluid consumption, I have plenty of hot drinks and raw honey.

In avoiding high protein meals and simple sugars, nuts and seeds, dairy is also important to avoid.

Making it a point to eat more than normal, the typical daily intermittent fasting is not the best strategy when sick.


What are your favorite cold and cough remedies and supplements?


Your Friend in Health

Mark Stein


[Get The Essential 3 Sugars and Fat for Every Health Optimizer]