What's The Difference Between Pesto And Pasta Sauce?

Pesto sauce vs pasta sauce

It might seem blatantly obvious, but we regularly encounter confusion over the difference between pesto and pasta sauce. Here we're looking under the bonnet of each to see how they compare from a nutritional, calorie, and taste point of view.

NOTE: All figures quoted are representative of existing sauces for sale in the UK, but they will vary considerably from brand to brand.

First, let's set the goal posts
The elephant in the room is that pesto is a sauce commonly served with pasta, so that makes it a pasta sauce, right? Yes, but when Brits say "pasta sauce," what they're usually referring to is the generic, tomato-based sauce popular in Italian-American cuisine that has kept many students alive on a minuscule budget.

Let's choose our pasta sauce
We want to be clear about what we're comparing, which is complicated by the fact that Italian cuisine boasts dozens of different tomato-based sauces. We love the rich and spicy arrabbiata, the anchovy and caper-based puttanesca, and the guanciale-lased amatriciana. However, the simplest of them all is pomodoro, and that's the one we're going to be using as our control here.

Let's choose our pesto sauce
There are so many different kinds of pesto on the market, including the bright red, sun-dried tomato one that is visually similar to pomodoro. For the sake of this article, though, we're talking about pesto Genovese, the most authentic pesto of all.

Similarities between pesto and pasta sauce
Other than being synonymous with Italian cuisine and making great accompaniments to pasta and pizza, that's where the comparisons end.

Differences between pesto and pasta sauce
There are almost too many differences to list, but the ingredients, texture, flavour, calorie content, and nutritional content of the two sauces are completely different. That is why you simply can't substitute one for the other.

Let's start by seeing how they compare, calorie-wise. Because a little pesto goes a long way, we're recommending a single serving size of around 50g. For the pasta sauce, we're allowing just over 100g per person.

Ingredients and calories in a single serving of tomato sauce

Ingredient Grams Calories
Tomatoes 100 22
Olive oil 2.5 20
Garlic 2.5 2
Basil 1 <1
Salt pinch <1
TOTAL 106 44

Ingredients and calories in a single serving of pesto

Ingredient Grams Calories
Olive oil 20 165
Basil 18 4
Pine nuts 7.5 50
Parmesan 7.5 32
Pecorino 5 22
Garlic 1 1
Salt pinch <1
TOTAL 60 274

So, as you can see, even though both sauces contain olive oil, garlic, and basil, the pesto contains over six times more calories than the traditional pasta sauce.

Of course, this is either a good thing or a bad thing, depending on whether you're more interested in flavour and nutrition or your waistline. Before we jump to the conclusion that pasta sauce is clearly healthier than pesto, it's important to look at the nutritional values of each sauce and see how they compare.

Difference in nutrition between 100g pesto and 100g pasta sauce

Nutrition Pasta sauce Pesto
Fat 2.5g 42g
   saturates 0.4g 7.5g
Carbohydrate 8g 7.5g
   sugars 6.5g 1.4g
Protein 1.5g 6.4g
Sodium 0.9g 1.8g

It's no great surprise that pesto has a shockingly high fat content compared to regular pasta sauce. Dieticians and proponents of the Mediterranean diet are always telling us that olive oil is high in "good" monounsaturated fat. That is true, but what they normally fail to mention is that it also contains high levels of saturated fat, usually about 13% of its weight. That's before you've even factored in the nuts and cheese, which are also high-fat ingredients.

A higher sugar content is to be expected with pasta sauce, especially if made with the sweeter varieties of tomatoes, but that's natural sugar and not at a high enough level to lose any sleep over.

There's one more important comparison to be made, which is what levels of vitamins and minerals each sauce contains. The percentages below show how much of your daily requirements you get from a single serving of sauce.

How much of your recommended daily number of vitamins and minerals do you get from one serving?

Vitamins Pasta sauce Pesto
Vitamin A 16% 10%
Vitamin C 20% 24%
Vitamin D 0% 6%
Iron 9% 15%
Calcium 6% 33%
Potassium 8% 4%

As you would expect, pesto's wider variety of ingredients means it does slightly better in the vitamin and mineral stakes. Pesto outsmarts tomato sauce in many of these, but the pasta sauce still provides a sizeable chunk of your recommended daily targets.

In conclusion
Pesto and pasta sauce are chalk and cheese in almost every way, even though they both taste great and are at their finest when paired with top-quality pasta. However, they're not as interchangeable as people may think. There's no doubt that pasta sauce is considerably healthier from a calorie and fat content perspective, but we're outlandishly biased and think pesto wins hands down in the flavour department.