Nicotine in Food: How Much is in Tomatoes and Potatoes? 

Nicotine is a naturally occurring alkaloid found in plants of the Solanaceae (nightshade) family.

While tobacco (Nicotiana tabacum) has the highest concentrations, trace amounts are also present in common foods like tomatoes, potatoes, peppers, and aubergines.

The reason? Evolution. Nicotine acts as a natural defence mechanism, helping plants fend off hungry insects.

Research has shown that plants with higher nicotine levels are less likely to be eaten, giving them a survival advantage.

While the nicotine levels in common foods like tomatoes and potatoes are tiny compared to tobacco, their presence is a leftover trait from millions of years of evolution. It’s a reminder that nature has its own way of ensuring survival.

Today, nicotine isn’t just sourced from plants. Advances in science mean that nicotine can now be created in the lab – synthetic nicotine – without the use of tobacco. 

Nicotine isn’t exclusive to tobacco—it’s present in several everyday foods. 

Here’s how common foods stack up in terms of nicotine concentration:

(Source: Journal of Agricultural and Food Chemistry, 1999)

To put this into perspective, an average diet provides around 1,400 nanograms (ng)of nicotine per day from food sources, with higher consumers (95th percentile) reaching up to 2,250 ng/day.—a fraction of what’s found in a single cigarette.

Some green and black teas contain trace amounts of nicotine, with levels in tea leaves varying widely—sometimes exceeding those found in Solanaceae fruits.

Now, let’s take a closer look at one of the most-searched foods: tomatoes.

Yes, but before you worry, let’s put things into perspective.

A medium tomato (~125g) would contain an estimated 337 - 2,012 ng of nicotine, according to the Journal of Agricultural and Food Chemistry, a minuscule amount compared to a single cigarette, which can contain as much as 20,000,000 ng—over 50,000 times more than a tomato.

While nicotine occurs naturally in some foods, dietary intake is significantly lower than nicotine exposure from tobacco products and is not considered to have comparable effects.

So while nightshade vegetables do contain trace amounts of nicotine, they’re nowhere near the levels found in tobacco and tobacco products.

Tomato-based products also contain trace amounts:

• Tomato sauces: 4,500 - 6,200 ng/kg
• Tomato ketchup: 5,800 - 10,300 ng/kg

Potatoes contain nicotine, but in lower amounts compared to tomatoes. Most of it is concentrated in the skin, while little to none is found in the flesh. So if you've been peeling your potatoes, you’ve been leaving most of the nicotine behind.

Here’s a general breakdown of nicotine levels in some common vegetables:

• Potatoes: 3,300 - 11,500 ng/kg (mostly in the peel)
• Aubergines (eggplants): Typically very low or undetectable levels
• Peppers: 3,700 - 9,000 ng/kg

While these amounts are tiny compared to tobacco, they’re a natural part of these plants' chemistry.

Tea leaves contain nicotine, with levels ranging from 163,800 ng/kg to 1,593,100 ng/kg (dry weight). However, brewing extracts only a fraction of this, with brewed tea containing 3,800 - 4,200 ng/L.

However, brewing significantly reduces nicotine levels. Only 20-25% of the nicotine in tea leaves is extracted into the liquid, with some teas showing undetectable amounts. Based on research, brewed tea contained:

• Assam Black Tea: 4.2 μg/L (4,200 ng/L), 21.3% extracted
• Darjeeling Black Tea: 3.8 μg/L (3,800 ng/L), 27.7% extracted
• Other Teas (Earl Grey, Ceylon Orange Pekoe, etc.): Nicotine was either not detectable or too low to quantify

While tea leaves have higher nicotine content than vegetables, the actual amount in a brewed cup is minimal—far lower than dietary intake from some foods and insignificant compared to smoking.

Let’s put these numbers in context. If you ate 1 kg of potatoes, you’d consume anywhere from 3,300 to 11,500 nanograms (ng) of nicotine—still thousands of times less than a single cigarette, which contains as much as 20,000,000ng in one cigarette.

Even for heavy vegetable eaters, dietary nicotine is minimal compared to active smoking. However, some research suggests that dietary nicotine intake could slightly influence nicotine and cotinine levels in body fluids—something to consider in passive smoking studies.

Cooking methods may affect nicotine levels in food.

While boiling could result in nicotine leaching into the water, research suggests nicotine is stable under heat, meaning cooking may not always significantly reduce levels in food..

Interestingly, French fries have been found to contain slightly higher nicotine levels than raw or boiled potatoes due to their lower water content.

A study published in Annals of Neurology examined the potential link between consuming Solanaceae vegetables – such as peppers, tomatoes, and potatoes – and Parkinson’s disease risk. The researchers found an inverse association between Parkinson’s and the consumption of these vegetables, particularly peppers. 

While the study found an inverse association, it did not establish a causal link, and further research is needed to understand this relationship.

People who ate peppers two to four times per week had a 30% lower risk of developing Parkinson’s compared to those who ate them less frequently. This association was most apparent in individuals who had never used tobacco or had smoked for fewer than ten years.

While these findings suggest a possible neuroprotective effect of dietary nicotine or other compounds found in Solanaceae vegetables, the study does not establish causation. Further research is needed to confirm these results and understand the underlying mechanisms.

For most people, dietary nicotine isn’t something to worry about. The amounts are tiny compared to tobacco products. However, the fact that it exists at all is fascinating.

It shows how deeply nicotine is woven into the natural world—not just as something humans consume but as a chemical that plants evolved for survival.

So, the next time someone asks, "Is there nicotine in tomatoes?"—the answer is yes. But unless you’re eating kilos of them daily, it won’t make a difference to your nicotine