Tag Archive for: diet

Eve Lahijani

Eve Lahijani graduated from UCLA with a B.A. in Economics and Business and went on to earn her Masters in Nutritional Science at CSU Los Angeles. She is now a registered dietitian for Vitamineve, a nutrition counseling service, and a nutrition health educator at UCLA. Eve’s Fiat Lux seminars on body image and proper nutrition have given many UCLA freshmen the tools necessary to maintain a healthy relationship with food.

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What hooked you on cooking?
I love learning about eating behavior. What, how and why people eat is intriguing to me. Especially when the eating is not related to physical hunger.
The coolest example of science in your food?
The process of denaturing an egg white and turning that into a soufflé is like magic to me.
The food you find most fascinating?
Ice cream is cool. Couldn’t help myself with that pun 🙂 I do appreciate the endless array flavors, textures, colors and combinations that can be created!
What scientific concept–food related or otherwise–do you find most fascinating?
How complicated eating behavior and food has become for some people (especially in harmful ways including over and under-eating and other compulsive eating behaviors) – and each individual’s process of understanding, simplifying and ultimately healing their relationship with food.
Your best example of a food that is better because of science?
I love Boysenberries and they are a blackberry/raspberry hybrid. Thank you science! And of course seedless watermelon.
We love comparing the gluten in bread to a network of springs. Are there any analogies you like to use to explain difficult or counter-intuitive food science concepts?
Yes: Eating in a balanced way is like a pendulum in a grandfather clock. You know, it swings back and forth. If the pendulum swings really far in one direction, due to the laws of physics it will swing far back in the opposite direction. Same holds true with eating. That is, if someone restricts (or goes on a diet) it pushes the pendulum too far in one direction so the better someone gets at depriving themselves the more likely the pendulum would swing far back in the opposite direction which may result in binges, cravings or overeating.
How does your scientific knowledge or training impact the way you cook? Do you conduct science experiments in the kitchen?
I like to plan to have well balanced meals that include components that bring about satisfaction. So I like to make sure my cooking involves carbohydrates, protein and fat – as well as fruits and vegetables. My science experiments include cupcake decorating along with trying new recipes with ingredients I get from the farmers market.
One kitchen tool you could not live without?
Sharp knife
Five things most likely to be found in your fridge?
Oranges, soy milk, Brussels sprouts, peanut butter, eggs and garlic so I guess that’s six!
Your all-time favorite ingredient?
Does chocolate flavored coconut ice-cream count as a food ingredient?
Your standard breakfast?
It’s always evolving. Right now I am into a mushroom, onion and garlic omelet or whole grain waffles with peanut butter. Whatever I choose I usually include some fruit and/or milk.

Cheese Holes & “Imaginary Meals”

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As it turns out, the holes in Swiss cheese may be from hay particles found in milk, say Swiss scientists. Also, scientists in California have developed a diet drug called Fexaramine, which may trick the digestive system into burning fat without food. Read more

Lard Legacy: Does Your Diet Doom Your Child’s Health?

Cheeseburger with Fries [photo credit: TheCulinaryGeek]

Cheeseburger with Fries [photo credit: TheCulinaryGeek]

Now you can feel even more guilt about how that greasy cheeseburger might affect your future. A study by the National Institutes of Health suggests eating a high fat diet may also impact your child’s health1.

Growing evidence links increased caloric and fat consumption to the rise in immune-mediated diseases, like arthritis, food allergies, and inflammatory bowel disease2. These diseases result from abnormal swelling and inflammation that occur when the immune system produces exaggerated responses or reacts to false signals. Studies suggest the high fat consumption typical of western diets may be responsible for confusing our immune systems. For example, dietary fats promote inflammation and trigger immune responses specific to bacteria3.

Because much of this evidence is based on short-term or population studies, for this study, Myles and collaborators explored the longer-term effects of increased parental fat consumption on their offspring’s immunity using mice1. Specifically, scientists fed a high fat “western” diet to one group and a low fat control diet to the other. After giving birth, their pups were fed the control diet and exposed to a battery of tests examining their immune response. Compared to the control diet, the western diet had 10% more calories from fat, twice as many carbohydrates, and a higher ratio (as much as 15:1) of omega 6 to omega 3 fats. While both omega fats are essential, healthy diets contain a close balance (2:1) of the animal-derived omega 6 fats relative to the fish- and vegetable-derived omega 3 fats.

While the mice pups showed no differences in weight or blood sugar, the pups whose parents had western diets surprisingly showed significantly lower immune function: these pups were less resilient to bacterial related disease. They had higher mortality rates from internal infections and more severe skin infections. Furthermore, their skin cells displayed a lower level of bacterial defense proteins. Additionally, their colons and spleens did not work as effectively. The colons of these animals, which are critical sites for developing the immune system, showed exaggerated inflammation when exposed bacterial toxins. Both their colons and spleens showed lower levels of immune cells and proteins.

B0008203 E.coli on the surface of intestinal cells

E.coli on the surface of intestinal cells [Photo Credit: Wellcome Images]

Interestingly, researchers suggest that the diet itself did not directly cause the compromised immunity of these mice. Instead, they conclude that the western diet negatively impacted their gut microbiome—the sum of all bacteria present in their gut. In follow-up experiments, pups fed the western diet showed normal immune function if their parents were fed the control diet. Furthermore, DNA characterization of mouse stool revealed that pups from parents on western diets had less diverse bacteria than control pups. Increased fat consumption may have changed available nutrients and limited the bacteria in the parents on western diets. Because mothers shape their offspring’s microbiomes during the birthing and nursing process, pups of parents on the western diet received less diverse bacteria. Therefore in follow-up experiments, the western diet did not affect the immunity of the pups whose mothers ate control diets, because they already had received diverse microbiomes.

Changes in the microbiome may impact the immunity of the pups because of the “hygiene hypothesis”; this essentially suggests we have become too clean. Because we are not exposed to enough bacteria and other immune system triggers growing up, our immune systems don’t develop as extensively as those exposed to a more diverse range of microorganisms. The ‘hygiene hypothesis’ has been fueled by research showing that children in homes with more bacteria have lower asthma and allergy rates. A similar scenario was recapitulated for the immune compromised pups in this study. Final experiments with the mice showed that when the researchers raised pups from both parental groups in the western and control diet together, they both displayed similar bacterial diversity and immune function. By living with the pups with more diverse bacteria, the immune compromised pups exhibited increased diversity in their microbiome and negated the effects of their parents’ western diet. In other words, this result may suggest that even if you lived on a diet of greasy cheeseburgers, your kid’s may still have healthy immune systems if they are rolling around in the dirt with the kids whose parents stuck to their kale and whole grains!

While this study is promising for the hygiene hypothesis, more research is necessary to understand this effect in people. For example, these mice had simpler microbiomes and diets than the average human. It is unclear how this complexity may change the effect for people. Additionally, while this study only looked at fat consumption, other factors such as genetics can impact microbiome diversity and the respective impact on immunity. In any case, assuming this research translates, it suggests eating a lean turkey burger now, may help save your kids from arthritis, food allergies, or inflammatory bowel disease in the future.

References cited:

  1. Myles, I.A. et al. 2013. Parental Dietary Fat Intake Alters Offspring Microbiome and Immunity. Journal of Immunology. 191 (6) 3200-3209.
  2. Kau, A.L. et al. 2011. Human nutrition, the gut microbiome and the immune system. Nature. 474: 327-336.
  3. Calder, P.C. 2011. Fatty Acids and Inflammation: The Cutting Edge Between Food and Pharma. European Journal of Phamacology. 668 (Suppl. 1): S50-S58
  4. Gereda, J.E. et al. 2000. Relation Between House-dust Endotoxin Exposure, Type 1 T-cell Development, and Allergen Sensitisation in Infants at High Risk of Asthma. Lancet 355: 1680-1683

Vince ReyesAbout the author: Vince Reyes earned his Ph.D. in Environmental Engineering at UCLA. Vince loves to explore the deliciousness of all things edible.

Read more by Vince Reyes


Big Soda & Food Perspectives

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An advocate for anti-obesity and healthful diets worked at PepsiCo to change the way food companies marketed junk food. Also, our understanding of how what we eat affects our biology may change with an alternative perspective on food as a hormone.
Read more

5 Things About Eating Healthfully

Dr. Dena Herman stopped by the 2013 Science and Food course to make smoothies and teach us about the molecules of food and nutrition. During her lecture, Dr. Herman shared several fascinating facts about eating healthfully. Here are 5 interesting facts relating to nutrition: Read more

Super Antioxidant Fruit Smoothie

If you take a look at the Nutrition Facts panel on your favorite snack, you can learn a lot about the different molecules in your food. These molecules—fats, proteins, carbs, vitamins, and minerals—are essential for our health: they provide energy for our bodies and can be recycled to form the molecular building blocks of our cells. Many of these molecules even promote specific molecular processes: Vitamin C helps build the collagen in connective tissue [1], while iron allows oxygen to bind red blood cells and be transported through the body [2].

NutritionFacts

But there’s an entire class of nutrients you won’t find listed in the Nutrition Facts: phytonutrients. While phytonutrients (also called phytochemicals) are not essential for our survival, they can have beneficial effects on our health. Trendy “superfoods” are often high in phytonutrients like resveratrol, flavonoids, or antioxidants.

This fruit smoothie recipe from Dr. Dena Herman packs a big punch of antioxidants thanks to a generous serving of antioxidant-rich berries. Antioxidants are a large group of chemicals that have the ability to counteract a process called oxidation. A material is “oxidized” when it loses electrons through a chemical reaction; antioxidants can impair this process by giving up electrons and becoming oxidized themselves. For example, apples that are cut and exposed to the air will quickly turn brown as oxygen interacts with and oxidizes molecules in the fruit’s tissue. Lemon juice can prevent this oxidative browning because it contains antioxidant molecules like Vitamin C.

In our bodies, oxidation can lead to cellular damage by breaking down important molecules like proteins, fats, and even DNA. Molecules that promote oxidative damage not only come from environmental factors like air pollutants, smoke, and UV radiation, but can also come from our own bodies as a byproduct of many cellular and metabolic processes. Our bodies are equipped to deal with moderate amounts of damage; however, extensive “oxidative stress” can wreak havoc on our cells and may contribute to the development of cancer, insulin resistance, and several cardiovascular and neurological diseases [3,4]. Consuming foods rich in antioxidants is thought to help counteract such harmful oxidative stress.

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Dr. Herman prepares her Super Antioxidant Fruit Smoothie during a 2013 Science & Food course lecture.

The Recipe:
Makes about 4-6, 8 oz glasses

1 package silken tofu or soft tofu
1–1½ bananas
2 cups mixed frozen berries*
2–3 tbsp apple juice concentrate
Water or unfiltered apple juice, enough to blend

*Other types of frozen fruit will work, but do not include citrus as it will curdle with tofu. Berries are used in this recipe because they are a great source of antioxidants.

  1. Blend all ingredients in a blender until smooth.
  2. Adjust to desired consistency by adding more water or unfiltered apple juice.
  3. Serve immediately and enjoy!


Online Resources

  1. USDA Agricultural Research Service, “Phytonutrient FAQs”
  2. Harvard School of Public Health, “Antioxidants: Beyond the Hype”
  3. NIH MedlinePlus, “Antioxidants”
  4. Scientific American, “Is the Free-Radical Theory of Aging Dead?”
  5. NIH Research Radio Podcast on Resveratrol


References Cited

  1. Van Robertson WB, Schwartz B (1953) Ascorbic acid and the formation of collagen. J Biol Chem 201: 689–696.
  2. Dallman PR (1986) Biochemical basis for the manifestations of iron deficiency. Annu Rev Nutr 6: 13–40. doi:10.1146/annurev.nu.06.070186.000305.
  3. Houstis N, Rosen ED, Lander ES (2006) Reactive oxygen species have a causal role in multiple forms of insulin resistance. Nature 440: 944–948. doi:10.1038/nature04634.
  4. Figueira TR, Barros MH, Camargo AA, Castilho RF, Ferreira JCB, et al. (2013) Mitochondria as a Source of Reactive Oxygen and Nitrogen Species: From Molecular Mechanisms to Human Health. Antioxidants Redox Signal 18: 2029–2074. doi:10.1089/ars.2012.4729.

Liz Roth-JohnsonAbout the author: Liz Roth-Johnson is a Ph.D. candidate in Molecular Biology at UCLA. If she’s not in the lab, you can usually find her experimenting in the kitchen.

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The Molecules of Food and Nutrition

Nutrition specialist Dr. Dena Herman introduced UCLA students to the molecules of food and nutrition as part of our 2013 Science and Food course. We learned all about essential nutrients, were introduced to the exciting new world of phytonutrients, and even got to make smoothies! Check out the highlights:


Vince ReyesAbout the author: Vince C Reyes earned his Ph.D. in Civil Engineering at UCLA. Vince loves to explore the deliciousness of all things edible.

Read more by Vince Reyes


Dena Herman

Dena Herman, RD, PhD, MPH, is an Adjunct Assistant Professor in the Department of Community Health Sciences at the UCLA Fielding School of Public Health. Her research has focused on improving dietary quality among low-income populations, as well as the development of interventions to reduce childhood obesity.

Dena-Herman

What hooked you on science? On food?
My dad was a chef for Nathan Pritikin, a nutritionist and longevity research pioneer who showed that cardiovascular disease was reversible with diet.
The coolest example of science in your food?
I am not sure it is the coolest, but I have always been fascinated by gels and emulsions. For example, vinaigrette dressing: you take 2-3 liquids and simply by the order in which you mix them they become and emulsion, something thicker than what you started with. The same principle applies to a roux: dry + liquid + heat = creamy sauce. How cool is that?
The food you find most fascinating?
Injera (Ethiopian flat bread).
What scientific concept–food related or otherwise–do you find most fascinating?
Currently I am fascinated with the “-omics.” Genomics, epigenetics, nutrigenomics, etc., and the idea that we are what our grandmothers ate (the idea of life-course health development).
Your best example of a food that is better because of science?
I can’t think of one. I believe the best foods are whole foods that have not been “adulterated” by science, i.e. Frankenfoods.
How does your scientific knowledge or training impact the way you cook? Do you conduct science experiments in the kitchen?
I have two sons (9 years old and 12 years old). The kitchen is always an experimental station, whether trying new combinations of ingredients to create exciting colorful mixtures (questionably edible), or figuring out ways to make things explode.
One kitchen tool you could not live without?
Vitamix.
Five things most likely to be found in your fridge?
Plain yogurt, cilantro, chili peppers, kale, raspberries.
Your all-time favorite ingredient?
Citrus, especially lemons and limes.
Favorite cookbook?
My German cookbooks. They take the simple and make it fabulous.
Your standard breakfast?
A kale, blueberry, and tofu shake. Phytonutrient-rich and protein ready.