Several studies have looked at human’s uncanny ability to always find room for dessert, and they’ve all come up with a similar answer. We do have extra room for dessert, mainly because of something known as sensory-specific satiety.
Satiety is essentially the quality of being full and sensory-specific refers to a combination of the taste, appearance, smell and texture of whatever you’ve been eating, or are about to eat.
According to Dr. Barbara Rolls at the Penn State University Laboratory for the Study of Human Ingestive Behavior, who’s been studying sensory-specific satiety since the 1980s, it comes as a result of chemicals which stimulate the brain’s reward center, producing pleasurable feelings when we eat.
These pleasurable feels, however, gradually decline as you continue eating. “The decline in pleasure you derive from food is specific to the food that you’ve been eating,” says Dr Rolls. “Or to other foods that are similar. So, while you might lose your appetite for that food, a different food will be appealing. That’s why you always have room for dessert.”
Professor Rolls’ research has shown that while we can get sick of eating the same food over a period of time, our appetite miraculously rebounds when we switch foods, say, from a pizza to a chocolate sundae.
In fact, one of her first studies was an experiment in which participants were given a four course meal. One group of participants received four courses of the same food, whereas the other received four different dishes.
The results showed that the second group consumed around 60% more calories than the group who received four identical courses, because they stayed interested in the foods, and gained pleasure from the variety.
Dr. Rolls reckons that it’s an evolutionary tactic that human’s developed to keep them healthy. A healthy diet needs to be varied, therefore, our brains have evolved to reward a varied diet: to tell us that changes in what we consume are good.
“We’re omnivores,” Dr Rolls explains. “And we need to eat a variety, it helps guarantee you will eat the variety of nutrients you need. Change in appeal during a meal keeps us going, keeps us eating.”
What we perceive as the feeling of being full, or satisfied, can often simply be a chemical cocktail which tells us our brain has “lost interest” in that particular food. A plate of fries is, at first, irresistible, but by the last fry, the enjoyment has faded.
Sensory specific satiety shows over and over again that the body has different limits for different foods and, “It’s the reason most of us manage to eat a balanced diet even if we don’t have nutritional knowledge,” Dr. Rolls said. “Variety is our friend in terms of nutritional balance.”
Over the years, Dr. Rolls has asked countless adults and children to fill up on savory foods. When offered a second serving, study subjects were often too full to eat much more. But when they were then presented with cookies, bananas or raisins, they always had room for another bite.
While sensory specific satiety allows you to keep eating new foods, eventually your body will tell you to stop eating. After about 1,500 calories in one sitting, the gut releases a hormone that causes nausea.
It’s why you’ll eat more French fries with condiments than you do without. Or why you’ll eat more ice cream if you’re offered multiple flavors than when offered only one.
But you can use it for good, too. Children eat more vegetables when they’re served a variety of types together, versus when they’re presented with a single veggie.
The satiety signal is particularly strong in children and diminishes with age. In studies by Dr. Rolls, children were allowed to eat unlimited quantities of M&Ms. But once they were full, they had a strong response to being offered more. “These little kids said, ‘These taste yucky. I don’t like them anymore,’” Dr. Rolls said. “We’d never seen as strong a response in adult subjects.
The reason for the pronounced difference in response by age isn’t clear, Dr. Rolls said. It may have to do with a natural decline in sense of smell and appetite as we get older. Or it could be that a lifetime of eating highly processed foods interferes with our natural satiety signals.
On top of this, our stomachs can actually get used the eating past the initial ‘full’ feeling, meaning you need more food to feel satisfied.
“Yes, our stomach and physiology have an ability to adsorb nutrients and energy to excess. Presumably this was a great survival mechanism in times when food was plentiful you could eat and your body would store what it could,” according to Russell Keast, a professor in sensory and food science and the director of the Center for Advanced Sensory Science at Deakin University in Melbourne, Australia.
Sugar stimulates a relaxation reflex, so something sweet can decrease the pressure on the stomach and reduce the sensation of being full. In other words, a sweet dessert allows the stomach to make room for more food.
The sweet dessert relaxes the stomach and allows greater capacity, but when it decides to constrict it can create uncomfortable feelings. Your body is doing what it can to push through digestion and the uptake of nutrients, and at the same time sending signals to the brain to stop eating.
“But as we know, there is a delay from swallowing the food and the uncomfortable fullness. Why don’t we learn. Possibly because it is not a critical-to-life illness, just a function of plentiful times. Again, our biology from millions of years of evolution ensure we can absorb foods when they are plentiful,” says Russell Keast.
Unfortunately dessert stomach is a real thing. While it may not be a physical stomach, the reward chemicals that your brain produces have a similar effect. Those chemicals tell you that “new food” is interesting and good, and you should eat it, at the exact same time that they’re telling you that “old food” (or food you’ve already eaten) is boring, and we’ve had enough of it.
The biggest downside of this variety effect is that food makers have taken notice. It’s the reason marketers have created variety packs and bundle multiple foods together in “value meals”.
“It’s of great interest to food companies who want to sell you more food and get you to eat more food,” Dr. Rolls said. “But you can also engineer your eating environment to have this work for you. Nobody wants to eat a half a plate of broccoli, but if you fill half your plate with a variety of vegetables and fruits, in that case, variety is a good thing.”
Psyllium husk comes from a shrub-like herb called Plantago ovata, which grows worldwide but is most common in India. Each plant can produce up to 15,000 tiny, gel-coated seeds, from which psyllium husk is derived. It also sometimes goes by the name ispaghula.
People use psyllium as a dietary supplement. It is available in the form of husk, granules, capsules, or powder. Manufacturers may also fortify breakfast cereals and baked goods with psyllium. Psyllium is best known as a natural laxative. It is the main active ingredient in Metamucil.
Psyllium husk powder is an edible soluble fiber and prebiotic. It’s often referred to as a bulking fiber because once it is ingested, it expands, forming a gel-like mass by drawing water in from the colon. It then promotes easy, healthy elimination by sweeping waste out of the colon more quickly and efficiently.
Because of its excellent water solubility, psyllium can absorb water and become a thick, viscous compound that resists digestion in the small intestine. Its resistance to digestion allows it to help regulate high cholesterol, triglycerides, and blood sugar levels. It can also aid weight management and relieve mild diarrhea as well as constipation. Unlike other sources of fiber, the body typically tolerates psyllium well.
Psyllium can help current diabetics as well as people trying to prevent diabetes. Eating dietary fibers like psyllium husk can assist in maintaining healthy glycemic balance. People with diabetes have to maintain a balance of insulin and blood sugar (glucose). Specifically, researchers have found taking psyllium before meals can significantly improve your fasting blood glucose.
One study evaluated psyllium seed husk fiber’s effect on lipid and glucose levels as an adjunct to dietary and drug therapy in patients with type II diabetes. The study found that taking psyllium daily can help patients with type II diabetes control their blood sugar without negative side effects.
Numerous studies have shown that fiber like psyllium, taken as part of a healthy diet, can help lower a person’s risk of heart disease. Psyllium can affect your heart by lowering blood pressure, improving lipid levels, and strengthening heart muscle.
Psyllium has been shown to improve high blood pressure. Hypertension affects 30 percent of the population and is a preventable condition. In a randomized clinical trial, six months of supplementation with psyllium fiber significantly reduced both systolic and diastolic blood pressure in overweight people with hypertension.
Obesity is the most prevalent health issue affecting all age groups, and it leads to many serious health problems, including diabetes and chronic heart disease. Psyllium husk is on the list of medicinal plants that have been shown to significantly decrease body weight. Psyllium husk can be very helpful in maintaining and achieving a healthy weight since it encourages a feeling of satiety when it is consumed.
Constipation is a very common health issue. Chronic constipation is especially common in adults older than 60 years, and symptoms occur in up to 50 percent of nursing home residents. Additional fiber intake in the form of psyllium is recommended by scientific studies to improve symptoms and provide natural constipation relief. Psyllium is recommended over magnesium-based laxatives, which should be avoided due to potential toxicity.
When combined with water or another liquid, psyllium husk swells and produces more bulk, which stimulates the intestines to contract and helps speed the passage of stool through the digestive tract. Psyllium has also been found to be superior to docusate sodium for softening stools by increasing stool water content and has greater overall laxative efficacy.
Since psyllium seed husk helps make elimination easier, it also helps naturally treat hemorrhoids, which are often the result of constipation. Psyllium can also be used to help relieve mild-to-moderate diarrhea. It’s beneficial to diarrhea sufferers because it soaks up a significant amount of water in the digestive tract, which helps make the stool firmer and slower to pass through the system.
Psyllium helps with maintaining healthy cholesterol levels. In a double-blind, placebo-controlled parallel study, all subjects maintained their usual diets, which provided less than 300 milligrams of cholesterol per day and approximately 20 percent of energy from protein, 40 percent from carbohydrates and 40 percent from fat. The study found that eight weeks of treatment with psyllium reduced serum total cholesterol levels by 14.8 percent, low-density lipoprotein (LDL) cholesterol by 20.2 percent and the ratio of LDL cholesterol to high-density lipoprotein cholesterol by 14.8 percent relative to baseline values. The reductions in total cholesterol and LDL cholesterol became progressively larger with time, and this trend appeared to continue at the eighth week.
- For adults and children over 12 years of age, take 1 teaspoon mixed into a liquid of your choice 1-3 times daily.
- For children 6-12, the recommended dosage of psyllium husk powder is a half teaspoon 1-3 times daily.
- Once the recommended serving of whole psyllium husks or psyllium husk powder is mixed well into at least eight ounces of liquid, it will thicken up into a gel-like consistency (this is normal) and it should be consumed immediately. If the mixture is too thick, simply add more liquid. Per serving, whole psyllium husks (one tablespoon) and psyllium husk powder (one teaspoon) are usually both around 15-30 calories with 3.5 to six grams of dietary fiber.
You can also purchase psyllium in capsule form. The amount of psyllium husk per capsule varies by company but typically contain around 500-625 milligrams per capsule. Follow the directions on the packaging for best results.
It is best to start by taking one serving of psyllium husk each day and gradually increasing to three servings per day if needed so the body can adapt. If minor gas or bloating occurs, reduce the amount you consume daily until your system adjusts.
Psyllium can interact with several medications. It may affect the absorption of:
- Tegretol (carbamazepine)
- Lanoxin (digoxin) (Take one hour before or four hours after psyllium.)
- Glumetza (metformin) (Take psyllium at least 30 to 60 minutes after taking metformin.)
- Zyprexa (olanzapine)
Tell your healthcare provider and pharmacist about all the medications you take, both prescription and over-the-counter, before starting a new supplement.
How to Buy
You can find psyllium in one or more forms at any health store and many online retailers. You can purchase whole psyllium husks, ground psyllium husk powder or psyllium husk capsules.
Some people find the whole husks to be more effective, especially when it comes to constipation, while others like the finer consistency of the powder. The powder is made by grinding the husks down so the gel ultimately produced is finer and has less of a grainy texture.
Similar to flaxseed supplements, it’s pretty much a matter of personal preference. Either way, when purchasing any psyllium supplement you should always make sure that the product is 100 percent pure, which means it is free of gluten, sugar, artificial flavors, artificial colors and fillers.
How to Store
All psyllium seed husk products should be stored at room temperature away from heat and light. Make sure to keep the supplement tightly closed to protect it from humidity.
How to Cook
The best way to use psyllium husk powder is to bake with it. It functions as a thickener, binding agent, and texture enhancer, all in one. Recipes usually call for small amounts of powder (most commonly 2-6 tablespoons, depending on the recipe). It is the crucial ingredient in gluten free bread baking. It acts as a binder, and it gives gluten free bread dough the elasticity, flexibility and extensibility it needs so you can actually knead and shape it without any problems.
Psyllium is a great natural alternative to gluten, questionable xanthan gum, and other unhealthy and expensive binding agents used in baking.
When using psyllium as a binding agent in baking, you need to include additional liquid in your recipe to compensate for the water-absorbing ability of psyllium. It’s a good idea to let your dough or batter sit for a few minutes to give the psyllium a chance to gelatinize, and then you can add the appropriate amount of liquid for your desired consistency.
Homemade Vegan Gluten-Free Bread
Healthy Girl Kitchen
- 3/4 cup brown rice flour
- 3/4 cup quinoa flour
- 1 cup chickpea flour
- 5 tbsp tapioca or arrowroot flour
- 1 tsp baking powder
- 1/2 tsp baking soda
- 1 tsp sea salt
- 2-3 tbsp everything seasoning
- 3 tbsp psyllium husk
- 2 cups water
- 1 tablespoon of herbs (optional) I use rosemary, oregano and thyme or make a dill loaf with fresh dill.
- Preheat oven to 350 degrees F. Prep a baking sheet with parchment paper. Combine psyllium husk powder and water and whisk immediately. It will thicken up right away. Set aside for 10 minutes.
- Combine all the dry ingredients in a large bowl if you’re kneading by hand or using a hand mixer. I used a kitchen aid mixer with the dough hook. Mix together.
- Pour the psyllium husk mixture into the dry ingredients. It will take 5-10 minutes for the dough to form. If the dough is too sticky/wet, add 1-2 tbsp chickpea flour. If it feels too dry, add 1-2 tablespoons water.
- Shape the dough into the bread shape you want.
- Bake for 60 minutes. Remove from the oven and let it cool completely before cutting into it.