The Science of Eating: Raw vs. Cooked

The Science of Eating: Raw vs. Cooked

Updated: May 24, 2024Veronika Larisova

Food's role in human evolution, culture, and health is undeniably pivotal. Historically, the debate around raw versus cooked food consumption has evolved in tandem with scientific understanding. The distinction, however, isn't merely binary. Different foods necessitate varied approaches: while some, like potatoes and legumes, require cooking for safe consumption, others, such as many vegetables, retain maximum nutritional value when consumed raw or minimally processed. From a biochemical standpoint, cooking facilitates various reactions, enhancing digestibility, flavour, and texture and introducing beneficial compounds like resistant starches in cooled cooked potatoes. Conversely, high-temperature cooking, especially with seed oils, can generate potentially harmful compounds and degrade essential vitamins and enzymes. Given these complexities, our focus should shift from generalised advice to a nuanced understanding of optimising nutritional benefits through selective cooking practices.

 

Raw Food

Raw foods preserve natural enzymes that aid digestion, such as those found in papaya and pineapple, which are deactivated by heat. They also retain a full spectrum of vitamins and minerals, including heat-sensitive nutrients like vitamin C and certain B vitamins. Phytochemicals and antioxidants, crucial for combating oxidative stress, remain intact in raw fruits and vegetables, ensuring an unaltered nutrient profile. Additionally, raw foods avoid the formation of harmful by-products that cooking, particularly at high temperatures, can produce.

However, raw foods risk harbouring harmful bacteria and parasites, particularly in raw meats like sushi or steak tartare, increasing the risk of food borne illnesses. Digestively, some raw foods, such as cruciferous vegetables, can be challenging to process, and lightly steaming these can improve digestibility while preserving nutrients. Moreover, raw foods may contain antinutrients like lectins, phytic acid, and oxalates, which can interfere with nutrient absorption and digestion. Cooking and soaking foods like beans, legumes, and grains are recommended to reduce these antinutrients' effects

 

Cooked Food

Cooking can enhance the bioavailability of certain nutrients, such as increasing the beta-carotene content in carrots, which our bodies convert to vitamin A. It also improves digestibility by breaking down plant cell walls, making nutrients easier to absorb, as seen in boiled or roasted potatoes. Additionally, cooking and cooling foods like potatoes or rice can transform some starches into resistant starches, which are beneficial for gut health. The Maillard reaction, responsible for browning and creating complex flavours in foods like seared steaks and toasted bread, enhances the taste profile, adding to the enjoyment of meals.

However, cooking can lead to the loss of certain nutrients, such as vitamin C and other heat-sensitive vitamins and minerals like A, B, polyphenols, potassium, magnesium, zinc, and glucosinolates. Light steaming is recommended to minimise nutrient loss. Cooking at high temperatures, particularly in unstable seed oils, can produce harmful compounds like Advanced Glycation End-products (AGEs) linked to inflammation and cancer. Avoiding grilling, charring, and reheating seed and vegetable oils and using acidic substances like lime juice during cooking can help reduce AGE formation.

 

Certain foods require a special mention because they are not so black and white

Cooking Oils

It's important to choose the right oils for cooking. Cooking in seed oils can produce AGEs, which can be harmful. Reheating seed oils is highly inflammatory and should be avoided at any cost. Animal fats such as tallow or ghee and oils with high smoke points, like avocado or coconut oil, are better for high-temperature cooking.

Air-Dried Meat

Techniques like air-drying meats, as seen in biltong, preserve the food and concentrate flavours. These methods often increase protein density, providing a nutrient-rich snack with a lower risk of pathogens than raw meats.

Inbetweeners: fermented foods

Fermented foods introduce an intriguing twist in the raw vs. cooked debate. While they aren't traditionally "cooked" using heat, they aren't entirely "raw" in the standard sense. Instead, they've been transformed by beneficial microorganisms, making them a unique category worth exploring.

Like cooking, fermentation can increase the bioavailability of certain nutrients. This natural preservation process can enhance levels of B vitamins, especially folic acid and riboflavin. Additionally, fermented foods can be a good source of probiotics, essential for gut health. Scientific research indicates that daily consumption of fermented foods is the best tool for increasing gut microbiota diversity. Yes, better than taking probiotic supplements or consuming lots of fibre!!! Fermentation also can break down food components that some people find hard to digest. For example, lactose in milk is broken down into simpler sugars during fermentation, making products like yogurt and kefir more digestible for lactose intolerant. While cooking kills off bacteria through heat, fermentation controls the food environment, promoting the growth of beneficial bacteria and suppressing harmful ones. Furthermore, fermentation can reduce antinutrients, compounds that can interfere with the absorption of essential nutrients. Phytic acid, for instance, which can inhibit the absorption of certain minerals, is broken down during the fermentation of grains and legumes.

Chief favourite fermented foods: sauerkraut, kimchi, kefir, and miso. We also love a good kombucha.

 

So, what’s the verdict? Raw or cooked?

Both raw and cooked foods have their rightful places on our plates. Incorporating a mix, like pairing a grass-fed steak with steamed vegetables and sauerkraut or enjoying air-dried meats such as biltong with raw sliced vegetables and kimchi, ensures a spectrum of nutrients and flavours.

 

Chief top tips:

  • Lightly steam your veggies, especially the cruciferous ones such as broccoli and cauliflower.
  • Eat raw salads with olive oil.
  • Use acidic marinades when cooking your meat, or squeeze some fresh lemon on it.
  • Slow and pressure cook your meat or make stews and stir-fries. Avoid grilling and chargrilling.
  • Ditch vegetable and seed oils and choose tallow, ghee or butter for cooking.
  • Soak beans, legumes, and grains before cooking them.
  • Eat potatoes and rice cooked and cooled for your gut health.
  • Have at least one serve of fermented foods per day.

 


    Veronika Larisova
    Co-founder, Nutritionist, Exercise Physiologist
    Follow Veronika on Instagram

 



 

References:

More articles

Comments (1)

  • Excellent article, very informative.

    ralph Rosaia

Leave a comment

Please note: comments must be approved before they are published