- Vitamin D3 Bioaccessibility from Supplements and Foods—Gastric pH Effect Using a Static In Vitro Gastrointestinal Model
- What are reasons for decreased gastric acid? - asked Perplexity AI Jan 2025
- How does aging affect stomach acid production? = asked Perplexity AI Jan 2025
- VitaminDWiki – Smoking reduces vitamin D - many studies contains:
- 4 related items in VitaminDWiki
Vitamin D3 Bioaccessibility from Supplements and Foods—Gastric pH Effect Using a Static In Vitro Gastrointestinal Model
Molecules Volume 29 Issue 5 10.3390/molecules29051153
Evangelia PasidiORCID andPatroklos Vareltzis *ORCID
Department of Chemical Engineering, Faculty of Engineering, Aristotle University of Thessaloniki, 54124 Thessaloniki, Greece
Vitamin D3 deficiency is a global phenomenon, which can be managed with supplementation and food fortification. However, vitamin D3 bioaccessibility may depend on factors such as matrix composition and interactions throughout the gastrointestinal (GI) tract. This research focused on the effect of different matrices on vitamin D3 content during digestion, as well as the effect of pH on its bioaccessibility. The INFOGEST protocol was employed to simulate digestion. Three different types of commercial supplements, two foods naturally rich in vitamin D3, and three fortified foods were investigated. High-Performance Liquid Chromatography was used to determine the initial vitamin D3 content in the supplements and foods, as well as after each digestion stage. The results indicate that the foods exhibited higher bioaccessibility indices compared to the supplements and a higher percentage retention at the end of the gastric phase. The pH study revealed a positive correlation between an increased gastric pH and the corresponding content of vitamin D3. Interestingly, exposing the matrix to a low pH during the gastric phase resulted in an increased intestinal content of D3. Vitamin D3 is more bioaccessible from foods than supplements, and its bioaccessibility is susceptible to changes in gastric pH. Fasting conditions (i.e., gastric pH = 1) enhance the vitamin’s bioaccessibility.
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What are reasons for decreased gastric acid? - asked Perplexity AI Jan 2025
Several key factors can lead to decreased gastric acid production (hypochlorhydria):
Medical Conditions
Atrophic Gastritis
The most common cause involves inflammation of the stomach lining, typically resulting from autoimmune disorders or H. pylori infection 4 8
Infections
H. pylori bacteria is particularly significant, as it neutralizes stomach acid and can damage acid-producing cells 1 9
Age-Related Factors
People over 65 have the highest risk of developing low stomach acid, as the stomach naturally produces less acid with aging 1 6
Medications
Long-term use of certain medications can reduce stomach acid production:
Nutritional Factors
- Zinc deficiency, as zinc is necessary for stomach acid production
- Poor diet leading to vitamin deficiencies
- High sugar intake 3 5
Other Contributing Factors
Stress
Chronic stress can significantly decrease stomach acid production 1 6
Surgical Procedures
Certain operations, particularly gastric bypass surgery, can reduce acid production capacity 1 7
Lifestyle Factors
Autoimmune Conditions
Conditions that damage stomach acid-producing cells, including autoimmune gastritis and pernicious anemia 9 10
How does aging affect stomach acid production? = asked Perplexity AI Jan 2025
The relationship between aging and stomach acid production is more complex than traditionally believed:
Normal Acid Production
Contrary to common belief, aging itself does not significantly decrease stomach acid production 1 2
Studies show that nearly 90% of elderly people can adequately acidify their gastric contents, even in an unstimulated state 2
Contributing Factors
Atrophic Gastritis
The apparent decline in acid secretion among elderly populations is primarily related to a higher prevalence of chronic atrophic gastritis, rather than age itself 1
Digestive Changes
The aging digestive system experiences several changes that can affect acid-related processes:
- Slower digestion rates, causing digestive acids to remain in the stomach longer 6
- Decreased production of protective stomach juices that shield against harsh digestive acids 6
- Reduced muscle tone in the lower esophageal sphincter 4
Clinical Implications
While aging alone may not reduce acid production, older adults are more susceptible to:
- Bacterial overgrowth due to medication-induced hypochlorhydria 5
- Increased sensitivity to medications affecting stomach acid 8
- Greater risk of complications from acid-related conditions 6
Risk Factors
Elderly individuals may experience decreased acid production due to:
- Use of acid-reducing medications like PPIs and antacids 9
- Higher prevalence of H. pylori infections 9
- Chronic stress effects on the digestive system 9
VitaminDWiki – Smoking reduces vitamin D - many studies contains:
Two pathways are often proposed for how smoking decreases vitamin D:
1) Smoking decreases Calcium. and Vitamin D is used up in replacing the Calcium
2) Smoking injures the body, and vitamin D is used up in repairing the body
It appears that taking Vitamin D while smoking will:
1) Decrease the incidence of the many health problems associated with smoking - even lung cancer
2) Decrease the desire to smoke (perhaps take fewer smoking breaks?)
3) Increase breathing capacity
Opinion: If you must smoke, have recently smoked, or are getting 2nd hand smoke:
take Vitamin D and perhaps Omega-3
They will extinguish much of the inflammation caused by inhaling tobacco smoke.
Vitamin D should also help people quit smoking
1) Reduces weight gain associated with quitting smoking
2) Reduces depression associated with quitting smoking