When we consider healthy eating, we think of eating more fruit and vegetables. However, to lose weight, accumulated fat or decrease potential diseases as a result of high sugar levels, most fruits inhibit a person's efforts towards any of these ends. Would this make fruits a dietary enemy?
Of course not. Just as you can use a dietary protocol according to your needs, the same goes for legumes and fruits.
What Does Your Body Read When You Consume Fructose (Sugar from Fruits and some vegetables) and Glucose (Sugar into Which Carbohydrates are Converted)?
Sugar metabolism occurs when the energy contained in the food we eat is converted into glucose, the fuel for the body. The cells of the body can use glucose directly for energy, and most cells can also use fatty acids or fat for energy, if glucose is not available.
Fructose, glucose, sucrose, galactose... all those words with that ending infer that they are sugar of some kind and that once digested they will pass into the bloodstream in the form of glucose which is the only brand our body knows. But be warned, not all sugars are the same.
Glucose and Fructose are Metabolised Differently:
Glucose in the blood stimulates the pancreas to release insulin so that the cells (anywhere in the body) can take up this glucose to obtain the energy needed to carry out all the daily activities we set out to do. After this, glucose returns to normal levels, but insulin will have switched off the use of fat for this purpose as it has given priority to glucose. In addition, glucose that has not been used for this purpose will be stored as glycogen in the muscles and as lipid in the fatty tissues of the body. Glucose goes everywhere in the body.
Fructose also enters the bloodstream from the gut, but first goes to the liver, which pre-processes it to see if it is converted to glucose or fat. The liver can eventually release glucose and fat into the blood or store it in glycogen or fat stores.
What is the Difference in Absorption Between Glucose and Fructose?
Glucose is used by virtually every cell in the body, including the brain, whether you are in a state of ketosis or not. Every cell has the capacity to use glucose.
Note: when you do a ketogenic cycle where you consume very little carbohydrate, as your body depletes its glucose stores, your liver begins to produce ketones, i.e. your body begins to use stored fat as fuel, which is known as a state of ketosis.
Fructose is metabolised very differently as the liver is the only organ that can process and metabolise it. Fructose cannot be utilised by all cells in the body and its presence completely inhibits the production of ketones in the liver.
Since glucose can be used by every cell in the body, when we consume glucose, we have the ability to burn it faster. But since the body cannot use fructose because it is over there in the liver, when we consume it and do not use it mainly in physical activity, it tends to be converted into free fatty acids and triglycerides, and eventually into fat.
Now, when we consume carbohydrates, our body absorbs glucose, i.e. simple sugars that come from carbohydrates, and chains them into a formation called glycogen and then stores them in the musculoskeletal system and a little of it in the liver. The interesting thing is that muscle tissue does something different with the glycogen stored there: it only uses it when we are exercising and/or need physical energy for an activity.
Both Carbohydrates and Proteins Trigger an Insulin Response
There is a big difference between a food that raises blood sugar (or has a high glycaemic load) and foods that only trigger an insulin response.
When we consume sugar, insulin is produced naturally, and the pancreas needs to produce that insulin so that the sugar in the bloodstream is absorbed by the cells where it needs to be used. The problem with a person who has diabetes is that they don't produce the necessary insulin and that sugar just floats around in the blood.
But be warned: it's not just carbohydrates that stimulate insulin production, protein does too. In fact, protein is considered one of the most insulinogenic foods (it improves insulin sensitivity).
Nutrition scientists have long known that fibre-rich foods, such as salads, slow down gastric emptying (the rate at which food leaves the stomach). Thus, fibre-rich foods slow the transport of glucose and other nutrients into the small intestine for absorption into the blood.
Proteins and fats also slow gastric emptying. Proteins have the added advantage of stimulating a hormone called glucagon-like peptide 1 (or GLP1).
When protein from food reaches the intestinal cells, this hormone is secreted, further slowing gastric emptying. The hormone also affects the pancreas, where it contributes to the secretion of the hormone insulin, which absorbs glucose from the blood.
What Happens When You Sequence Food Intake?
Most scientific research on whether eating in a particular order influences glucose spikes has provided encouraging results when a "preload" of fibre, fat or protein is given before the meal. Typically, the preload is liquid and is given about 30 minutes before carbohydrates.
A study in 2005 showed that consuming a protein (in this case whey) before consuming the rest of the meal produced an insulin response, causing blood glucose to fall.  Further studies indicate that consuming pea protein isolate (preferably liquid) half an hour before your first meal can be very effective not only in lowering blood sugar, but also because it does not have an inflammatory effect.
Now you have the tools to know at what time and according to your type of diet, it is good for you to eat your vegetables and fruits. However, I will show you the fruits and vegetables that are most commonly used in the most popular dietary approaches.
Fruits and Vegetables that Best Match Your Eating Protocol
If the fruit comes with its inherent fibre as is the case when eating a whole fruit, up to 30% of the sugar present in that fruit will not be absorbed. Instead, it will be metabolised by microbes in the gut, which can improve microbial diversity and help prevent disease. Fibre will also result in a slower rise in blood glucose, which has been shown to have positive health effects.
You can consume fruits and vegetables strategically and according to your dietary purposes. For example,
Ketogenic cycle-friendly fruits and vegetables
One avocado (216g) contains 4 grams of sugar.
180 grams of tomatoes contain 5 grams of sugar.
144 grams of strawberries contain 8 grams of sugar.
110 grams of grapefruit contain 10 grams of sugar.
154 grams of watermelon contain 11 grams of sugar.
160 grams of melon contain 11 grams of sugar.
100 grams of kiwi fruit contain 12 grams of sugar.
The vegetables that are best for you if you are following a ketogenic protocol are:
Kale, spinach, Chinese chard, celery, cucumber, courgette, cauliflower, asparagus, broccoli, green beans, green bell pepper and Brussels sprouts.
Fruits and Vegetables For a Low-Carbohydrate Diet
Raspberries - Half a cup (60 grams) contains 3 grams of carbohydrates.
Blackberries - Half a cup (70 grams) contains 4 grams of carbohydrate.
Strawberries - Eight medium (100 grams) contain 6 grams of carbohydrate.
Plum - One medium (65 grams) contains 7 grams of carbohydrate.
Tangerine - One medium (75 grams) contains 8 grams of carbohydrate.
Kiwi - One medium (70 grams) contains 8 grams of carbohydrate.
Cherries - Half a cup (75 grams or about 12 cherries) contains 8 grams of carbohydrate.
Blueberries - A half cup (75 grams) contains 9 grams of carbohydrates.
Cantaloupe - One cup (160 grams) contains 11 grams of carbohydrate.
Peach - One medium-sized peach (150 grams) contains 13 grams of carbohydrate.
The most consumed vegetables in a low-carb protocol resembles that of the ketogenic diet. So, mainly kale, spinach, celery, cucumber, cauliflower, asparagus, green pepper, Brussels sprouts and of course, the different varieties of lettuce.
Fruits and Vegetables when Following a Mediterranean Diet
Fruits and vegetables endemic from the Mediterranean countries are of course apples, oranges, strawberries, grapes, dates, figs, melon, peaches and avocado.
The most consumed vegetables that can suit you are tomatoes, broccoli, cauliflower, onions, carrots, olives, Brussels sprouts, cucumbers, potatoes, sweet potatoes, and turnips.
In addition, some legumes such as beans, peas, chickpeas, peanuts, and lentils.
Fruits and Vegetables when Following Time-Restricted Feeding or Intermittent Fasting
A Time-Restricted Feeding (TRF) protocol requires that what you eat is packed with nutrients and meets your nutritional requirements as you will be consuming it for a limited time.
The key is mainly in the timing of breaking the fast and if you decide to include carbohydrates at that time, then in the form of a salad, but containing mainly good quality protein.
Fruits that provide a high concentration of nutrients include avocado, berries such as strawberries, blackberries, raspberries, cherries, and blueberries.
Vegetables, especially cruciferous vegetables such as cauliflower, broccoli, and Brussels sprouts. Also, tubers such as potatoes, cassava, and sweet potatoes.
Black beans and other legumes such as chickpeas, lentils, and peas.
Fermented foods such as sour cabbage, kimchi and miso.
Fruits and Vegetables for Athletes
- Berries are rich in antioxidants and help to maintain muscle strength.
- Bananas are one of the favourite fruits in the sports field as they are easy to transport, to consume and are also used as a thickener when preparing smoothies, providing density and texture.
- Cherries have high concentrations of antioxidants.
- Hydrating foods are perfect options when you lose a lot of fluid after a workout. Watermelon, celery, radishes, and peppers help you feel refreshed after a workout.
- Cruciferous vegetables such as broccoli, cauliflower, kale and rocket contain vitamins, minerals and antioxidants, but are also prebiotics, i.e. they feed the good bacteria in your gut flora.
- Sweet potatoes help lower blood pressure and contain many vitamins and minerals, such as potassium, iron, manganese, and copper.
Pulses are an easy food to incorporate into many dishes and are full of fibre, magnesium, protein, iron, and zinc. Beans and pulses, such as peas and lentils, are the perfect plant-based proteins for both vegetarian and omnivorous athletes because of their versatility and nutrients.
Fruits and Vegetables that Best Suit You According to Ayurvedic Medicine
Did you know that, according to your physiology, your physical characteristics and even your food tastes, you belong to one of the predominant Doshas of Ayurveda and that according to this ancient medicine certain foods would help you to rebalance your Dosha or body’s disturbances.
I strongly recommend you take the Ayurveda Test on my website, find out your Dosha and consider the foods that balance your body. You will be surprised to find that many of the fruits and vegetables according to your Dosha turn out to be among your favourites. Here is the link: https://en.johannakoelle.com/pages/ayurveda-test-to-find-your-dominant-dosha