The 9 Least Healthy Foods

Do you know which are the least healthy foods that you should avoid to reduce the risk of getting sick? We'll mention the main ones, as well as their effects.
The 9 Least Healthy Foods
Saúl Sánchez

Written and verified by el nutricionista Saúl Sánchez.

Last update: 24 June, 2023

Products that are really harmful to the body often appear in the diet. They usually have a good flavor, so their consumption generates some satisfaction at the organoleptic level. However, you have to avoid their intake on a regular basis. That’s why we are going to tell you which are the least healthy foods.

Keep in mind that one of the bases of the diet is variety. This means that some of the foods that we’ll show you can be consumed, although on a specific basis. If the supply of quality nutrients is ensured on a daily basis, resorting to an unhealthy product from time won’t bring about negative consequences.

The least healthy foods

We’ll now go on to talk about the foods that are the least healthy for the body. All of them are included within the group of industrial ultra-processed products. To ensure that the body works correctly, it’s always best to prioritize fresh products.

Sugary soft drinks

According to a study published in the journal Nutrients, regular consumption of sugary soft drinks causes problems at the cardiometabolic level. The added sugars that they contain inside cause insulin resistance in the medium term, which conditions weight gain and the development of inflammatory mechanisms in the body.

For this reason, it’s advisable to avoid the consumption of this type of beverage. Especially in children, their presence in the diet must be greatly limited. During the first stages of life, the foundations are laid for a correct future diet. It’s time to accustom children to the intake of fresh foods and vegetables, not ultra-processed ones.

In addition, it must be borne in mind that high doses of added sugars are even more harmful to a developing body. At the same time, it’s important to note that when these ingredients are administered in liquid form, their absorption is much faster, which has a negative impact on blood glucose levels.

Calorie-free soft drinks that have artificial sweeteners inside are also not a good option. These products have been shown to have a negative effect on the intestinal microbiota, reducing the density and diversity of the bacteria that inhabit the digestive tract. Therefore, digestion worsens and the incidence of inflammatory bowel diseases increases.

To this, we must add that the medium-term effects of many of the artificial sweeteners aren’t clear. We do know that in a short period of time, they affect metabolism and insulin sensitivity, but it’s unknown whether or not they’re really safe for kidney or liver function when chronic consumption of them is considered.


Among the less healthy foods is pastries.
Bakery products, despite being delicious, can be counterproductive to health. Their high content of trans fat is one of the many reasons.

Bakery products are considered very unhealthy. On the one hand, they’re made from highly refined flours. These products have a significant impact on blood glucose levels, causing pancreatic stress and insulin resistance, the precursor to type 2 diabetes.

The sugars they contain must be added. Simple carbohydrates are also capable of causing alterations in blood glucose levels, which in the long run translates into a greater risk of developing metabolic diseases. To avoid such a situation, it’s best to include complex carbohydrates in the diet, as much as possible.

Pastries have trans fatty acids inside. These elements are generated from the high baking temperatures, due to the transformation in the spatial arrangement of the molecules that make up the lipids. Nutrients go from cis to trans, something that’s considered very harmful to health.

There’s evidence that indicates that trans-type lipids are capable of promoting inflammatory mechanisms in the body. According to research published in the journal Diabetes & Metabolic Syndrome , their regular consumption is associated with a higher incidence of various chronic diseases such as diabetes, cancer, and cardiovascular diseases.

Keep in mind that saturated fats are more susceptible to trans transformation when heat is applied to them. This is due to the nature of their bonds, all of which are simple in type. Bakery products usually contain large amounts of butter to enhance their flavor, an ingredient that concentrates saturated fat. When the product is baked, trans lipids are generated.


For many years, several nutrition experts have claimed that moderate alcohol consumption could be beneficial for cardiovascular health. At present, we know that this isn’t true. This substance is considered toxic regardless of the dose consumed. Not even the tannins (chemical compounds) in grapes compensate for this effect in the case of wine.

In fact, the presence of alcohol in the diet increases the risk of suffering neurodegenerative, metabolic, and cardiovascular diseases in the medium term. This is evidenced by research published in the journal Alcohol and Alcoholism. For this reason, its presence in the diet should be restricted. The less you consume, the better.

The consumption of this type of drink in adolescents or young adults is of particular concern. When the brain is developing, the effect of the poison is even greater. In addition, it’s common during the early stages of adulthood to experience alcohol poisoning due to excessive intake, which increases the harmful effects.

We must warn of the dangers of combining alcoholic beverages with other energy drinks. Caffeine can mask the effects of intoxication at first, thus allowing for higher amounts of alcohol. Once the poison enters the blood, very negative alterations are generated.

Liquid yogurt

Yogurts are recommended foods in almost any diet. They have probiotic bacteria inside that have been shown to help improve digestive and intestinal health. However, on many occasions, these products are marketed with large amounts of added sugars inside.

This problem is exaggerated when it comes to liquid yogurt. The simple type carbohydrate content can be comparable to that of sugary soft drinks. Although these foods are denser from a nutritional point of view, an excessively high supply of glucose is still experienced, which impairs metabolic function in the medium term.

When it comes to consuming yogurts, the best option is always to opt for natural and whole ones. It’s not a good option to remove the fat from dairy. With this nutrient, a lot of the fat-soluble vitamins that are necessary to ensure the proper functioning of the human body are lost. In this case, we’d be losing a lot of quality.

Another good option is the intake of milk kefir. It’s possible to prepare this product with a semi-liquid texture, similar to that of drinkable yogurt. However, if sugars aren’t added and it’s prepared homemade, the quality is much higher. It’s a food that has probiotic bacteria inside.

Industrial tomato sauces

Homemade tomato sauce or tomato sauce recipes may contain a small amount of sugar as an ingredient. This product is added to balance the acidity of the vegetable, generating a better final flavor. However, industrial preparations have amounts of simple carbohydrates that are higher than desirable, which is why they’re considered unhealthy products.

The best option when it comes to consuming tomato sauces is to prepare them at home. Of course, you’ll have to take special care with the packaging and the preservation method. It’s always best to store the sauce in hermetically closed glass containers, which have gone through a water bath process to ensure a vacuum inside. This reduces the microbiological risk.

When using a commercial tomato sauce, it’s always preferable to opt for crushed tomato as such. In this case, there’s no addition of ingredients other than the fruit itself and ascorbic acid, which acts as an antioxidant and as a preservative. This itself is a high-quality product, as it contains vitamins and phytonutrients with antioxidant capacity.

An example of the latter is lycopene. This substance is able to help prevent cardiovascular diseases, according to a study published in the journal Atherosclerosis. It has an anti-inflammatory capacity, which protects against the development of problems such as atherosclerosis and the formation of plaques in the blood vessels that limit flow.

Fried nuts are among the least healthy foods

Nuts are considered very healthy foods when consumed natural. They have high-quality fatty acids, proteins, fiber, and essential micronutrients inside. Among the latter, we can highlight selenium, a compound with antioxidant activity. This is evidenced by research published in Advances in Clinical and Experimental Medicine.

However, the quality of these products varies when they undergo a frying process. Their organoleptic characteristics improve, but the energy value increases significantly. This can cause the consumption of nuts to generate an imbalance in the energy balance. If this is combined with other harmful habits, you can become overweight or obese.

At the same time, frying causes a part of the lipids present in nuts to change their configuration to a trans type. As we’ve explained previously, these elements are considered dangerous to health when consumed on a regular basis.

It’s important to note that the objective of dietary changes isn’t to eliminate the presence of trans fats in the diet, as even breast milk contains them. However, their contribution must be limited.

In this way, if you want to consume nuts, the best option will always be to choose the natural or toasted varieties. Roasting usually causes an inactivation of certain substances present in these products known as antinutrients. This improves digestion and reduces absorption problems for some minerals such as calcium and iron.

Also, it’s good to avoid the salty versions. Too much sodium in the diet could be counterproductive for those with a history of high blood pressure. This condition is considered one of the risk factors for the development of other cardiovascular diseases.


Commercial chocolate is another of the products considered less healthy. This is because, in its composition, cocoa is a practically residual element. The main ingredient is sugar, which generates metabolic problems when consumed on a recurring basis. In addition, commercial chocolates can contain additives, trans fats, and other elements that are harmful to health.

However, not all chocolates are categorized as poor-quality food. Those that have a high concentration of cocoa inside are positive for the human body. This element of plant origin is characterized by the presence of antioxidants inside. These substances help neutralize the formation of free radicals.

Among the most prominent antioxidants in bitter cocoa is theobromine. This has positive effects on cardiovascular health, as it’s capable of bringing blood pressure levels down. It also contributes to reducing inflammatory mechanisms, which protects against the oxidation of the lipid profile and against the agglutination of cholesterol particles.

When choosing a commercial chocolate, it’s always preferable to opt for those varieties with a cocoa concentration greater than 75%. Another option is to purchase this ingredient in powder form, in its bitter version. It can be added to many culinary preparations. Even if it’s combined only with milk, you get a drink with a high nutritional density.

Ice cream is one of the least healthy foods

Among the less healthy foods is ice cream.
Ice creams are frequently consumed on hot days, and they’re the favorite sweets at any age. However, except for artisan preparations, they contain high amounts of processed sugars.

There’s a substantial quality difference between artisan and industrial ice creams. The former has a moderate sugar content and don’t have additives inside. They contain fat, but this hasn’t been subjected to an aggressive thermal process, so it’s not considered harmful to health. The consumption of this kind of product on an occasional basis doesn’t generate major problems.

Industrial-type ice creams are one of the worst foods we can find. Their sugar content is excessive. At the same time, they have hydrogenated fats and additives that are doubtful for health. These products are capable of increasing the risk of developing diabetes and other metabolic problems in the medium term.

When opting for the consumption of ice cream, the best thing is always to resort to artisan elaborations. They can even be prepared at home without much difficulty. It’s only necessary to have quality fresh ingredients, being very sure to introduce fresh milk in the recipe.

At the same time, it should be noted that the industrial versions without added sugar aren’t a good option either. In this case, artificial sweeteners are used to add texture and a sweet taste. Most of them can trigger alterations in digestive function in the medium term.


The habitual presence of processed red meat in the diet is totally contraindicated for health. These preparations have poor-quality fats inside. In addition, it’s common for dubious preservative additives to be added, such as nitrites. These can increase oxidation in the internal environment.

As if this weren’t enough, many of the frequently consumed sausages have undergone a smoking process. During it, toxic substances can adhere to the meat, such as polycyclic aromatic hydrocarbons. These compounds have been associated with a higher incidence of various types of cancer, so it’s crucial to reduce their consumption as much as possible.

However, there are some varieties of sausages that can be included in the context of a healthy diet without major problems. We refer to those lean and little processed, such as Serrano ham and turkey breast. In any case, it’s important to check the labels to ensure the absence of nitrites and sulphites that tarnish their quality.

In the case of ham, it’s always advisable to use those pieces from animals raised in the wild. The feeding of the pigs is decisive when it comes to knowing the types of fatty acids that they’ll contain inside. For example, if pigs eat acorns throughout their lives, they’ll have a higher proportion of unsaturated fats.

Avoid the least healthy foods in your diet

Now you know which are the least healthy foods. These products have to be avoided whenever possible. Nothing happens if they appear on occasion, but in no case should their intake become routine. They have substances that are toxic or harmful to the body in the medium term.

Remember that health doesn’t only depend on a good diet. It’s important to promote other habits such as sports practice on a regular basis and a good night’s rest. With these practices, homeostasis is ensured in the internal environment, which reduces the risk of developing complex diseases in the medium term.

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