Easy Ways to Boost Fiber in Your Daily Diet

Contributors: Holly Larson, MS, RD

Published: March 01, 2021

Reviewed: February 26, 2021

Nic_Ol/Thinkstock

Fiber is an essential nutrient. However, many Americans fall short of the recommended daily amount in their diets. Women should aim for about 25 grams of fiber per day, while men should target about 38 grams, or 14 grams for every 1,000 calories.

Dietary fiber contributes to health and wellness in a number of ways. First, it aids in providing fullness after meals, which helps promote a healthy weight. Second, adequate fiber intake can help to lower cholesterol. Third, it helps prevent constipation and diverticulosis. And fourth, adequate fiber from food helps keep blood sugar levels within a healthy range.

Natural Sources of Fiber

Fiber is found in plant foods. Eating the skin or peel of fruits and vegetables provides a greater dose of fiber, which is found naturally in these sources. Fiber also is found in beans and lentils, whole grains, nuts and seeds. Typically, the more refined or processed a food is, the lower its fiber content. For example, one medium apple with the peel contains 4.4 grams of fiber, while ½ cup of applesauce contains 1.4 grams, and 4 ounces of apple juice contains no fiber.

By including certain foods, you can increase your fiber intake in no time. For breakfast, choose steel cut oats with nuts and berries instead of a low-fiber, refined cereal. At lunch, have a sandwich or wrap on a whole-grain tortilla or whole-grain bread and add veggies, such as lettuce and tomato, or serve with veggie soup. For a snack, have fresh veggies or whole-grain crackers with hummus. With dinner, try brown rice or whole-grain noodles instead of white rice or pasta made with white flour.

Here are a few foods that are naturally high in fiber:

• 1 large pear with skin (7 grams)
• 1 cup fresh raspberries (8 grams)
• ½ medium avocado (5 grams)
• 1 ounce almonds (3. 5 grams)
• ½ cup cooked black beans (7.5 grams)
• 3 cups air-popped popcorn (3.6 grams)
• 1 cup cooked pearled barley (6 grams)

When increasing fiber, be sure to do it gradually and with plenty of fluids. As dietary fiber travels through the digestive tract, is similar to a new sponge; it needs water to plump up and pass smoothly. If you consume more than your usual intake of fiber but not enough fluid, you may experience nausea or constipation.

Before you reach for the fiber supplements, consider this: fiber is found naturally in nutritious foods. Studies have found the same benefits, such as a feeling of fullness, may not result from fiber supplements or from fiber-enriched foods. If you’re missing out on your daily amount of fiber, you may be trailing in other essential nutrients as well. Your fiber intake is a good gauge for overall diet quality. Try to reach your fiber goal with unrefined foods so you get all the other benefits they provide as well.

Looking for credible nutrition information and recommendations? The Academy of Nutrition and Dietetics’ network of credentialed food and nutrition practitioners are ready to help!

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Should I be eating more fiber?

You probably know the basics about fiber: it’s the part of plant foods that your body cannot digest, and there are two types — soluble fiber and insoluble fiber. Both types of fiber are good for us.

Soluble fiber dissolves in water, forming a gel. It is the form of fiber that helps lower cholesterol levels, reduce the risk of heart disease, and regulate blood sugar levels. Soluble fiber is found in black beans, lima beans, Brussels sprouts, avocado, sweet potato, broccoli, turnips, and pears.

Insoluble fiber passes through the digestive system relatively intact, adding bulk to stools. It is the form of fiber that prevents constipation and regulates bowel movements, removing waste from the body in a timely manner. Insoluble fibers are found in whole wheat flour, wheat bran, cauliflower, green beans, and potatoes.

Despite these health benefits, most Americans get less than half the suggested amounts of daily fiber. The popularity of very-low-carbohydrate diets like the ketogenic or “keto” diet, the Atkins diet, and the Whole 30 diet, which may unintentionally decrease fiber consumption, hasn’t helped matters.

It may be time to give fiber another look.

New evidence confirms protective effect of fiber

A new analysis of almost 250 studies confirmed on a large scale that eating lots of fiber from vegetables, fruits, and whole grains can decrease your risk of dying from heart disease and cancer. Those who ate the most fiber reduced their risk of dying from cardiac disease, stroke, type 2 diabetes, and/or colon cancer by 16% to 24%, compared to people who ate very little fiber. The study also concluded that more fiber is better. For every additional 8 grams of dietary fiber a person consumed, the risk for each of the diseases fell by another 5% to 27%. Risk reductions were greatest when daily intake of dietary fiber was between 25 and 29 grams.

Two observational studies showed that dietary fiber intake is also associated with a decreased risk of death from any cause. Those eating the highest amount of fiber reduced their risk of dying by 23% compared to those eating the least amount of fiber. In these studies, the associations were more evident for fiber from cereals and vegetables than from fruit.

Weight control is another benefit of high-fiber diets. By helping you feel full longer after a meal or snack, high-fiber whole grains can help you eat less. In one large study, adults who ate several servings of whole grains a day were less likely to have gained weight, or gained less weight, than those who rarely ate whole grains.

Fiber: how much is enough?

On average, American adults eat 10 to 15 grams of total fiber per day, while the USDA’s recommended daily amount for adults up to age 50 is 25 grams for women and 38 grams for men. Women and men older than 50 should have 21 and 30 daily grams, respectively.

In general, it’s better to get your fiber from whole foods than from fiber supplements. Fiber supplements such as Metamucil, Citrucel, and Benefiber don’t provide the different types of fiber, vitamins, minerals, and other beneficial nutrients that whole foods do.

When reading a food label, choose foods that contain more fiber. As a rule of thumb, choose cereals with 6 or more grams of fiber per serving, breads and crackers with 3 or more grams per serving, and pasta with 4 or more grams per serving. Another strategy is to make sure that a whole-grain food has at least 1 gram of fiber for every 10 grams of carbohydrate. If you look for a 1:5 ratio, that is even better.

Ignore the marketing on front of the package labels. Just because a bread is labeled “multigrain” or “12 grain” does not mean it is a whole grain. The grains could be refined and the bread may be low in fiber. When you look at the ingredient list, make sure “whole” is the first ingredient.

Easy ways to get more fiber in your diet

Here are some strategies to increase fiber in your diet:

• Start your day with a bowl of high-fiber cereal.
• Add vegetables, dried beans, and peas to soups.
• Add nuts, seeds, and fruit to plain yogurt.
• Make a vegetarian chili filled with different types of beans and vegetables.
• Add berries, nuts, and seeds to salads.
• Try snacking on vegetables such as cauliflower, broccoli, carrots, and green beans. Serve them with a healthy dip such as hummus or a fresh salsa.
• Eat more whole, natural foods and fewer processed foods.

A few important tips as you increase your fiber:

• Do so gradually to give your gastrointestinal tract time to adapt.
• Increase your water intake as you increase fiber.
• If you have any digestive problems, such as constipation, check with your physician before dramatically increasing your fiber consumption.

Take a positive approach to eating more high-fiber foods. Beyond reducing risk of chronic disease, eating a variety of whole foods that contain good sources of fiber can be an easy and enjoyable way to keep you fuller longer and help control your weight. Fiber can expand your horizons with different tastes and textures, and can be a bonus to your health.

Information on optical fiber – Integra Cable

Integra Cable > Useful information > Information on fiber

Optical fibers used in the fiber optic cable brand “Integra Cable”

A is a single-mode optical fiber that complies with ITU-T G recommendation. 652.D
A – Single-mode optical fiber, compliant with ITU-T G.657.A recommendation
H – Non-zero dispersion-shifted single-mode optical fiber, compliant with ITU-T G.655 recommendation
B – 62.5 µm multimode optical fiber
M – 50 µm multimode optical fiber, compliant with ITU-T G.651.1

Attenuation at

G.

652 wavelengths. Standard single mode fiber

It is the most widely used single mode optical fiber in telecommunications.

Undispersion-shifted single-mode stepped fiber is a fundamental component of an optical telecommunications system and is classified by the G.652 standard. The most common type of fiber optimized for signal transmission at a wavelength of 1310 nm. The upper limit of the L-band wavelength is 1625 nm. Microbending requirements – mandrel radius 30 mm.

The standard divides fibers into four sub-categories A, B, C, D.

G.652.A fiber meets the requirements necessary for the transmission of information flows of STM 16 level – 10 Gbit / s (Ethernet) up to 40 km, in accordance with with G.691 and G.957 recommendations, as well as STM level 256, according to G.691.

G.652.B fiber meets the requirements required to carry information flows up to STM 64 according to G.691 and G.692 and STM 256 according to G.691 and G.959.1.

G.652. C and G.652.D fibers allow transmission in an extended wavelength range of 1360-1530 nm and have reduced attenuation at the “water peak” (“water peak” separates the transparency windows in the passband of single-mode fibers in the ranges 1300 nm and 1550 nm). Otherwise similar to G.652.A and G.652.B.

G.652.A/B equivalent to OS1 (ISO/IEC 11801 classification), G.652.C/D equivalent to OS2.

The use of G.652 fiber at higher transmission rates over distances of more than 40 km leads to a discrepancy in performance with the standards for single-mode fiber, requires the complication of terminal equipment.

Standard colors for optical cable fibers in the module

Optical fibers 13 to 24 are marked with ring marks in addition to the standard colors. At the request of the customer, other colors of optical fibers and modules may be allowed. If necessary, optical modules are replaced by filling cordels.

G.655. Non-Zero Dispersion Shifted Single Mode Fiber (NZDSF)

Non-Zero Dispersion Shifted Single Mode Fiber (NZDSF) is optimized for multi-wavelength transmission (WDM Multiplex Waveform and DWDM High Density Waveform) rather than a single wavelength. The fiber is protected by a double acrylate coating, providing high reliability and performance. The outer diameter of the coating is 245 µm.

Non-Zero Shifted Dispersion Fiber (NZDSF) is designed for use in backbone fiber optic lines and wide area communication networks using DWDM technologies. This fiber maintains a limited chromatic dispersion coefficient over the entire optical range used in wave multiplexing (WDM). NZDSF fibers are optimized for use in the wavelength range from 1530 nm to 1565 nm.

Recommendations divide fibers into three subcategories: A, B, C, which differ in terms of PMD, chromatic dispersion and operating range.

Category G.655.A optical fibers have parameters that ensure their use in single-channel and multi-channel systems with optical amplifiers (recommendations G.691, G.692, G.693) and in optical transport networks (recommendation G.959.1). Operating wavelengths and dispersion in this sub-category fiber limit the input power and their application in multi-channel systems.

Optical fibers of category G.655.B are similar to G.655.A. But depending on the operating wavelength and dispersion characteristics, the input signal power may be higher than for G.655.A. The requirements in terms of polarization mode dispersion ensure the operation of STM-64 level systems at a distance of up to 400 km.

The G.655.C fiber category is similar to G.655.B, but more stringent PMD requirements allow STM-256 level systems (G.959.1 recommendation) to be used on these optical fibers or to increase the transmission range of STM-256 systems. 64.

TIA/EIA-598 color coding

G.657. Low Radius Bend Loss Single Mode Fiber

G.657 version of high flexibility optical fiber is widely used in optical cables for laying in networks of high-rise buildings, offices, etc. Fiber G.657.A in its optical characteristics is completely identical to the standard fiber G.652.D and at the same time has half the allowable laying radius – 15 mm. G.657. B fiber is used over limited distances and has particularly low bending loss.

Single-mode optical fibers are characterized by low bending loss, are primarily intended for FTTH networks of multi-apartment buildings, and their advantages are especially evident in confined spaces. You can work with G.657 standard fiber almost like with a copper cable.

Two subcategories A and B which differ in core diameter and flexural performance.

For G.657.A fibers it is 8.6 to 9.5 µm and for G.657.B fibers it is 6.3 to 9.5 µm.

Macrobending loss standards are significantly tightened, since this parameter is decisive for G.657:

– ten turns of G.657.A subcategory fiber, wound on a mandrel with a radius of 15 mm, should not increase attenuation by more than 0.25 dB at a wavelength of 1550 nm. One turn of the same fiber, wound on a mandrel with a diameter of 10 mm, provided that the other parameters are not changed, should not increase the attenuation by more than 0. 75 dB;

ten turns of subcategory G.657.B on a 15 mm diameter mandrel, shall not increase the attenuation by more than 0.03 dB at 1550 nm. One turn on a mandrel with a diameter of 10 mm – more than 0.1 dB, one turn on a mandrel with a diameter of 7.5 mm – more than 0.5 dB.

ITU Recommendation G.657.A prioritizes compatibility with standard fibers over functionality (with ITU-T G.652D). Recommendation ITU-T G.657.B emphasizes bend insensitivity over compliance with G.652 standards.

Maximum attenuation versus bend radius at 1550 and 1625 nm

OM 1 and OM2. Standard multimode fibers with a core of 62.5 and 50 µm, respectively

Cables, patch cords and pigtails with multimode fibers of types OM1 62.5/125 µm and OM2 50/125 µm have long been used in SCS to provide data transmission at high speed and on relatively large distances required in highways. The most important functional parameters of MM fiber are attenuation and bandwidth ratio. Both parameters are defined for the wavelengths of 850 nm and 1300 nm, on which most of the active network equipment operates.

This is a specially designed multi-mode optical fiber used for Gigabit and 10 Gigabit Ethernet networks, it exists only with a core size of 50 µm.

OM4. New generation laser-optimized 50 µm multimode optical fiber

OM4 multimode fiber is now fully compliant with today’s fiber standards for next generation data centers and server farms. OM4 optical fiber can be used for longer links in new generation data networks with the highest data transmission performance. This fiber is the result of further optimization of the characteristics of OM3 fiber to give the fiber the characteristics to achieve 10 Gb/s data rates at a distance of 550 meters. OM4 fibers have an increased effective minimum modal bandwidth of 4700 MHz*km at 850 nm (compared to 2000 MHz*km of OM3 fiber).

Standard colors of optical modules in the fiber optic cable core layer

Optical modules are counted from the red module towards the green one.

Optical fiber standards

Edited: 12/24/2020

Given the great popularity of optical communication lines in the last few years, most of them are currently based on modern single-mode fibers. However, both single-mode and multimode fibers fall into many types and categories that conform to established standards and factory specifications. The article “Multimode and single-mode fiber optic cables” raises the main issues related to the difference between these types of optical fibers.

Specifications for various types and categories of fibers are contained in developed international standards. In addition, numerous factory standards and specifications are used in local markets.

Terminology and classification

The International Electrotechnical Commission (IEC TC86) technical committee 86 is responsible for international standardization in the field of fiber optics, which has defined the following type types:

• Multimode fibers, e.g. into groups (e.g. A1a.1 …)
• Single mode fibers, e.g. B1, B4, B6 …

However, the more popular markings are based on abbreviations:

• OM – optical multimode
• OS – optical single mode

Examples: OM1, OM2, OM3, OM4, OS1, OS2. Specifications defining specific transmission parameters will be presented later in the text.

The OM designation has become widespread, in contrast to the OS marking. In the case of single-mode variants, the names used by another international organization, the ITU (International Telecommunication Union), in particular the Telecommunications Solutions Standards Division (ITU-T), are more common.

ITU-T guidelines are widely known and used. “Characteristics of the transmission medium and optical systems” are included in the G.600-G.699 standard, optical fibers are described in the G.650-G659 standard. Each recommendation is for a specific fiber type.

Selected standards and recommendations

The following is a summary of selected standards for fiber optics.
ISO / IEC Standards:

The table below provides a simplified overview of the varieties of multimode fibers defined by the IEC standards.

OFL * – OverFilled Launch is a standardized fiber bandwidth measurement method in which the source uniformly directs light into all modes of multimode fiber (LED source).

EMB ** – Effective Modal Bandwidth – effective modal bandwidth of the center or offset (laser source illuminates a small part of the fiber core).

It is clear that the development of multimode fibers is in the direction of fibers that can carry more and more data. OM1 provides 10 Gb/s data transfer rates over very short distances (up to 33 meters), while OM4 allows 100 Gb/s data transfer up to 150 meters. However, given the current improvement in single-mode fiber, even the OM3 and OM4 varieties will rarely be used.

ITU-T Recommendation:

This large number of documents is the result of the rapid development of optical fiber due to the high demand for fast and long distance types of data transmission. Today, single-mode fiber is usually cheaper than multi-mode fiber. Such fibers are the future, and some exceptions may only exist in local systems, because devices that work with single-mode optical fibers are a little more expensive.

The ITU-T recommendations are much more stringent (or precise) than the transmission performance categories defined by IEC (OS1 and OS2). For example, the specifications required by OS2 are fulfilled by G.652.C fiber, which means that the G.652D fiber type has the best performance.

Single-mode fiber standards

Single-mode fibers, conform to the following standards:

• G.652 – defines 4 versions (A, B, C, D). G.652.C and G652.D versions have a reduced water peak (ZWP – Zero Water Peak), which allows them to be used in the wavelength range from 1310 nm to 1550 nm, supporting coarse wavelength division multiplexing (CWDM) transmission .
• G.652.D is a standard single-mode fiber (SSMF) designed for 10 and 40 Gbps systems (due to Reduced Polarization Mode Dispersion – PMD). It is currently the most popular optical fiber.
• G.655 – defines a fiber with characteristics specified at 1550 nm and 1625 nm, with a non-zero
  chromatic dispersion slope in these wavelength ranges. This type of optical fiber can support long-distance communication systems using dense wavelength division multiplexing (DWDM) transmission in the wavelength range from 1530 to 1625 nm.
• G.656 is a fiber designed for use in broadband systems using DWDM and CWDM, designed to operate in the wavelength range from 1460 nm to 1625 nm.
• G.657 – defines an optical fiber that produces a lower level of attenuation that is caused by bends. The minimum bending radius is reduced to 15-5 mm (depending on the version). G.657A fiber is compatible with G.652 fibers, G.657.B versions are not 100% compatible with other fibers, but have unique mechanical characteristics suitable for the most demanding installations.

How to compare all existing standards and recommendations?

The ITU-T recommendations are based on the IEC standards, however there may be minor differences in some versions.

It is worth mentioning another organization that unites a significant part of the telecommunications industry – the Telecommunications Industry Association (TIA). The activities and documents of the organization are best known in the USA, some standards were published earlier than in Europe.

Some comparisons:

Multimode fibers :

• OM1 – 62.5 / 125 – IEC60793-2-10 A1b – TIA 492-AAAA
• OM2 – 50/125 – IEC60793-2-10 A1a.1 – G.651.1 – TIA 492-AAAB
• OM3 – 50/125 – IEC60793-2-10 A1a.2 – G.651.1 – TIA 492-AAAC
• OM4 – 50/125 – IEC60793-2-10 A1a.3 – TIA 492-AAAD

Singlemode fibers :

• G.652A, B – 9/125 – IEC60793-2-50 B1.1
• G.652C, D – 9/125 – IEC60793-2-50 B1.3
• G.655 – 9/125 – IEC60793-2-50 B4
• G.657A – 9/125 – IEC60793-2-50 B6_a1
• G.657B – 9/125 – IEC60793-2-50 B6_a2

Parameters of selected single-mode fibers

G.652.D fiber is the most commonly used fiber in today’s systems due to its versatility and cost. Some standards, such as G.653, quickly fell into disuse due to application costs and limitations in the physical properties of the fiber.